No faulting Nat's wedding-venue choice, I thought, as I parked up in front of the impressive old pile – once a posh country house, now a posh hotel. I had just over an hour before the ceremony at 2 o'clock, and wondered if I could squeeze in a quick walk in the garden before getting ready. Little clusters of sharp suits and colourful dresses were already milling about. None of them looked my type socially, but then Nat and I hadn't seen each other since graduating fifteen years ago, and our lives had drifted apart. I still didn't know whether to be surprised she was getting married, and was only mildly so that it was to a man. What did surprise me was that she'd invited me at all: she'd hinted in the card that I owed it to her.

*

At the desk in the lobby, a receptionist in her mid-twenties with a neat heart-shaped angel plait in her light brown hair greeted me. The white blouse under her navy jacket was pleasingly tight-fitting; the badge on her lapel, I noticed as I glanced at her figure, said 'Isabel'. She twitched her jacket closed a little, but kept up her generous smile.

"Hello," I said in my interested-if-you-are voice, trying to keep my eyes on her face. "Eloise White. For Natalie...sorry, er, Alice Whitaker's wedding." For some reason, Nat was obviously using her middle name nowadays, and her mother's maiden name – although she'd still signed my invitation 'Nat'.

The receptionist nodded as if she'd been expecting me, and her smile widened in genuine pleasure. Which was nice (if a bit odd). "Good afternoon, Dr White." She tapped at her computer. "You're all paid up. Lovely." She pushed a room key across the counter with a nice but un-manicured hand. "Number 120."

I took the key, and wondered why – if she'd taken obvious care over her clothes, makeup and (especially) hair – she'd do such a cursory job on her nails. They were cut short and unpainted, as if she usually did something more practical than tapping a computer and smiling. I was also just starting to wonder how I'd managed to forget paying in advance, when she looked past me out to the sweeping gravel approach. "We'll have to move your car, I'm afraid."

"Might ruin the photos, huh?" I chuckled. "I know it's not exactly a babe-magnet, but it's not that ugly, is it?"

The receptionist's smile twitched slightly, but her eye was determined. "Sorry, ma'am, we need that space clear." She indicated a large bloke who was hovering at the desk. "Gary here can take it round the back." Her look and charming manner politely suggested it wasn't my place to argue. "Do you have everything with you?" She glanced at the small suitcase by my leg.

"Er, yes. Just this bag." I meekly surrendered my keys to Gary, who looked more like a bouncer than a hotel porter.

Isabel stood up and quickly straightened her navy skirt. "I'll show you to your room. I've something to deliver to that floor anyway." My protests were overruled by a ravishing, don't-argue smile. She palmed an envelope off the desk.

I followed her up the stately main staircase, admiring her legs through her thin black tights, and trying unsuccessfully to flirt my way through her business-like demeanour. Room 120 was a corner room at the end of the first-floor corridor, overlooking an orchard. It was much nicer than I'd expected, or thought I'd have paid for (if I had indeed paid), and the bed looked fun.

Isabel had accompanied me into the room, patiently waiting with her weight on one hip for me to stop talking. I asked about walking the grounds, and she recommended the path through the kitchen garden to the orchard, pointing out that it wasn't very far given that time was short. I told her I didn't think I'd paid, either; she politely but firmly reassured me the balance was not outstanding.

Eventually, I ran out of things to keep her talking. She glanced down the corridor, then shut the door and approached me in the centre of the room; for a second, I thought I'd got lucky. But she just handed me the envelope, although our hands did almost touch where we both held it for a moment. "The bride asked me to give you this for later, ma'am. Discreetly." She smiled at me quickly, and there was a flash of conspiratorial intimacy in her pretty eyes. "I'd be quick about that walk, if I were you, but the orchard is well worth a look." She slipped back out into the corridor, with another quick smile over her shoulder.

*

I was indeed quick about the walk, and the orchard was verdant, quiet and very pleasant. I resolved to take time later in my stay to enjoy it properly. In the here and now, I couldn't help feeling something a bit odd was going on. There was a whiff of tension in the air, at least from Gary and Isabel. Also, time was getting short.

*

Back in the room, while sorting my hair and makeup and squeezing myself into my best party frock and heels, I mentally itemised what was bothering me:

-Nat and I'd been on Christmas-card-if-you're-lucky terms for years, and the number of smartly-dressed people around suggested she wasn't lacking better friends; so why invite me?

-The hotel staff weren't quite right: Isabel was difficult to read, and slightly odd (if polite, efficient and cute); Big Gary looked very incongruous indeed.

-Why was the woman I knew as Natalie Simpson now calling herself Alice Whitaker? Was I even in the right place?

-What favour did Nat think I was repaying? The biggest favour she'd done me was in our first year at uni, giving me a cast-iron and much-needed alibi by making me stay in her room one night. It had, in retrospect, certainly saved my university career, and I was eternally grateful, but how was attending her wedding going to make up for it?

-Most immediately, what the hell was the envelope all about? It had a short message on it, in Nat's handwriting (which suggested it was actually her): Ells, Great you're here. No need to open this unless things go tits-up (they might). Nat xoxo

No-one had called me 'Ells' for years, so it was definitely Nat. But it was all very unlike my usually practical and upright former friend.

*

Grabbing my smart jacket and stuffing my room key, phone and purse into a sweet little shoulder bag, I made it halfway down the staircase about ten minutes before the thing was due to start. The lobby was buzzing, and there seemed to be some fuss towards where the ceremony would be. Two smart suits by the main doors were awkwardly sharing a mobile to hold a video-call with someone else. One was saying, "Yeah...Paul..." He drew his hand across his throat and made a croaking sound, then added, "Nah, no sign of Alice."

Paul, I knew from the invitation, was the groom. Or more accurately, it would seem, the late groom. Shit. That would screw up the plans a bit, for certain. And Alice/Nat was missing?

Isabel seemed to be on the reception desk phone, but she looked up and caught my eye. She looked carefully at me for a long moment, almost as if she was admiring my dress (it was a nice dress, but I thought it rather unlikely that she was just being sisterly, given who she was and the current awkward situation). She raised an eyebrow in recognition of me and pretended to fiddle with her hair, probably guessing I'd follow the movement. She'd guessed right, and her mouth twitched quickly as she caught my eye to check. Turning her head away from any onlookers, she made a very small, subtle gesture with her fingers along her cute plait to suggest I should retreat back upstairs. Then she put the phone down quietly and disappeared through a side door.

Sirens could be heard heading up the grand driveway. Randomly, I thought they had arrived very quickly: I had no way of knowing when Nat's fiancé had apparently been found dead, and Nat herself missing, but it didn't seem from the general air of shock like it had been long ago. The crowd's mood stiffened as several police cars skidded up to the entrance, their blue lights like a monochrome disco on the lobby walls. An ambulance wasn't far behind them.

As I backed onto the landing, someone touched my elbow. Big Gary said softly, "This is 'tits up', ma'am." He pushed me in the direction of my room. "In case you were wondering, for the envelope."

As discreetly as my heels would carry me in all the increasing fuss downstairs, I retreated to my room and tore the thing open. On the hotel's best headed paper was a note in Nat's handwriting: Ells, you're a true mate. Do as Gary asks. See you soon. Thanks, Nat xoxo

Which suggested to me that Nat was both OK – which was a huge relief – and that she had had an idea something like this would happen. Which made me wonder what the bloody hell I'd found myself involved with. Even to the extent that my invitation to attend was connected in some way?

*

Big Gary let himself silently into the room, making me jump. He was surprisingly light on his feet for a man his size. He crossed to the window. "Apologies, ma'am. Can't really explain now, but you'll have to trust me for a second." He glanced at his watch. "Gonna be a lockdown here any minute. We need to get you away before the uniforms start asking you silly questions. You climbed down a drainpipe before?"

"Er, no. Not much call for it as a university lecturer."

Gary threw the sash up and motioned me towards it. "It's not too difficult. And the boss got you this room special, so it's not too far to drop. Down the drainpipe there, and through the orchard, if you would. Might want to take them shoes off, though." He smiled briefly. "Nice car, by the way, ma'am, for what it is."

He bundled me onto the sill. I looked back as I took my heels off and felt for the drainpipe with my foot. It wasn't elegant, my dress wasn't exactly drainpipe-climbing gear, but I guessed Gary had more pressing things on his mind than a 35-year-old woman on a windowsill flashing him a bit of leg. "It's a ten-year-old hatchback, Gary."

"Yeah, ma'am. But it'll shift well enough when you put your foot down, and it's inconspicuous. Which is good, just now." He made sure I was steady against the wall and the downpipe before tying my heels to the strap of my bag and looping the strap over my wrist. "I'll make sure your stuff's sent on. Keep your head down through the kitchen garden, ma'am. Make for the bottom of the orchard and you should see your car. Izz should be there to meet you with the boss. The uniforms are gonna start crawling all over the place looking for her in a sec, so quick as you can, if you don't mind."

I had questions, but Gary started shutting the window. I had to descend the pipe to avoid getting my fingers squashed. In the end, I was quite pleased with both my speed and efficiency in getting down to the ground, with only a slight rip in my tights to show for it.

As I knew from my little walk earlier, the orchard was but a minute or so away, although this time I crept in a sort of brisk crouch. Skirting quickly along the hedges of the kitchen garden to conceal myself from the hotel windows, I got to the gate at the end and out into the orchard. There were now sounds of shouting from the hotel.

Trotting through the trees, I straightened up slightly and glanced back. A couple of uniformed police were starting to fan out from the hotel terrace. I didn't know if it helped that my dress was light green, amongst all those apple trees, but I ducked back down and started to run anyway.

In the lane behind the orchard was my car, idling, driver's door open. Isabel was hovering at the passenger door and Nat was bundled in the back, a coat over her bridal whites. Isabel's attention was mainly on the hotel behind me and up the lane, and she had a small revolver in her hand. I don't know anything about guns, but I assumed it was effective, despite its size. I suddenly had more questions, but found myself politely but firmly requested to take the wheel.

Isabel ducked briskly into the passenger seat. "Straight down the lane, ma'am, left at the end. Quickly, please." She twisted round to look behind us, and only turned back round once we'd turned off onto a smaller track. She tucked her pistol away in a discreet holster under her jacket and strapped herself in, letting her breath out heavily. A completely irrelevant part of my mind noticed how high her short skirt had ridden up her nice legs. She glanced at me, and tugged the skirt hem down a bit.

*

I stopped the car behind a tall row of poplars, and met Isabel's steely look before she could say anything. "I need to put my shoes on, I can't drive barefoot. Even heels would be better." She deftly untied them from my handbag and handed them over.

Nat touched my shoulder, while I thrust my feet into the shoes without bothering to do the straps up. "Good to see you again, Ells."

I grunted, and set off again. "Bloody odd way of going about it, Nat. We could've just had a drink sometime."

Undeterred, Nat went on, "Drop a right in about 200 yards. There's a gate at the bottom, which should be open for us. Turn left out of it."

I did, and no-one said anything until I was through the gate and on the road out of the village. As far as I could tell, we'd looped almost right around the hotel on some estate back roads and left by an obscure service access route. Out of the corner of my eye, I was aware of Isabel watching me drive. Just outside the village, I had to pull over to let an ambulance thrust past in the other direction, lights flashing.

"That's a bad sign, ma'am," she said.

"Usually is," I shrugged, assuming she was talking to me. She was certainly looking at me, though she had flicked a look in the rearview mirror as well.

"Hopefully not," replied Nat at the same time, and I realised Isabel had been talking to Nat. I also realised why Isabel and Gary had been calling me 'ma'am' all day, rather than the more usual 'madam' (or my actual name). They were in some sort of professional authority relationship to Nat, and must have transferred it to me by association. Gary had called her 'the boss', after all. Which brought all my questions back, with some urgency.

But as I was about to start asking them, I caught Isabel's eye again, and noticed a mixture of amusement and careful attention to my driving. I realised that it felt as if she was not just watching me all the time, but judging me. The feeling of helplessness, of not knowing what was going on, combined with the adrenalin, tipped over into irritation. "Stop watching me drive. It's very distracting."

She looked shocked at my tone for second then, to my surprise, blushed. "Sorry, ma'am. Didn't mean to put you off." She straightened in her seat, and seemed to be staring ahead out of the windscreen. As far as I could tell: she'd flicked her hair forward across her cheek.

"And please stop calling me 'ma'am'." My irritation died a little. "It just feels a bit...odd, you know?"

She glanced back at me and raised her eyebrows. After a moment, and again to my surprise, she smiled quite sweetly, and tucked her hair behind her ear again. "Of course." She nodded slightly backwards at Nat. "Force of habit. Would you prefer Dr White?"

"You could try Eloise." I also nodded backwards. "She calls me 'Ells', but I've never known why."

"All right." She hid her smile from Nat with her hair and held my eye for a moment while pretending to look straight ahead. "Once we hit the main road follow the signs to the A1, northbound." She shifted in her seat slightly, and unnecessarily tugged at her skirt hem again. "Thanks. Eloise."

*

Occasionally, either Isabel or Nat would glance behind, but there wasn't anything following us. We were almost at the A1 junction when Nat muttered, "That ambulance bothers me. We did have one standing by, didn't we?"

"Yes, ma'am."

I agreed with Isabel. "One turned up with the cops, just before Big Gary bundled me out of the window. I thought all that response was a bit quick for a normal 999 call..."

Nat hmm'd. "I don't like that. Unless it's going somewhere else? Bloody unlikely, though." She sighed. "The worst bit is not knowing."

I grunted again, and indicated to turn onto the slip road. "Funny you should say that, Nat. I feel a bit in the dark myself." I negotiated the transition from slip road to main carriageway, flashing my lights in thanks to a lorry who'd kindly moved lanes. The little pause gave me an opportunity to let the irritation flare higher inside. "I mean, who are you? Both you personally, with your Alice Whitaker shit, and all this..." I waved around vaguely, incorporating Isabel and making a deliberate show of pointing at the slight bulge of the gun under her jacket. "Who are Isabel and Gary? Who was your fiancé? Is he really a 'was'? It was your actual wedding, wasn't it? And if it's cold feet, fair enough, that happens apparently, but this is pretty bloody extreme by anyone's standards. What's with the cryptic notes? Why did I have to jump out of my room window? Had I even paid for it? Am I paying you back for that night in first year? I mean, Nat, seriously? What the fuck is going on?"

Isabel coughed lightly. "Sorry, Eloise, but would you mind driving a bit faster?"

"What the fuck? Dual carriageways are a 70 limit, if I remember my Highway Code correctly. Do you really want the bloody police to pull us over, just at the moment? After we've busted ourselves out of a hotel like something from a bloody film? Who do you think you are?"

She shot me a little smile, but then the steely-eyed receptionist persona was back. "I think we are the bloody police, Eloise. I'll do the talking, if you're pulled over."

I didn't doubt she would be very persuasive. I swore pointedly, then sighed and duly pulled over into the outside lane, accelerating as much as I dared.

Nat said, "Ells, I'm sorry. We will explain when we get where were going. Right now, though, that's our priority, and we kind of need you to do it quickly."

I grunted and focused on the road, nudging the car faster and faster within its limits (and mine, as a driver). Gary was right, though: it did fine at speed. I'd never known I could bomb along at 110mph in it with no problem. I realised that the adrenalin was still flowing through me – ever since my drainpipe escape – and fast driving was just topping it up. Despite myself, I found it quite exciting. The road and engine noise generally made any further conversation difficult.

Isabel pulled a phone out of her jacket pocket and checked something, resting it on her thigh as she suggested I should start slowing down for an exit. After a little while, when I was back below the speed limit, she said, "Next one, please. It should be in about a mile."

I took advantage of the reduction in road noise. "Nat, I know you can't talk about what's just happened, but can you at least tell me, is this about that night in first year?" Beside me, Isabel suddenly and carefully pretended not to listen.

Nat sighed. "Not really, Ells, but yes, if you like, you're paying me back for that. I wanted someone completely unknown in my current life as a back-up – needed you, as it turned out. Thanks for coming through. I'm sorry it's not what you were expecting."

"I didn't know what to expect." I sighed again. "But you know you're welcome. You know full well I wouldn't be where I am today without you."

Isabel cleared her throat again. "Sorry, Eloise, this exit. Right at the top of the slip road." I started indicating, and she put her phone away. "Don't mean to be rude, ma'am," she continued, addressing Nat, "But that must be one hell of a favour."

Nat snorted with amusement. "I'll let you explain this one, Ells."

"Nat had the room below me in halls in our first year at uni." I negotiated the roundabout at the top of the junction and turned onto a single-carriage A road. "We were sort of on casual chat terms at first, until one night she really saved my bacon. Will you tell me if I need to turn?" Isabel just nodded, so I went on. "I was attacked one night, on the way back from the off-licence. I shouldn't have taken the shortcut through the park. He groped me and tried to do more. Anyway, in the struggle, I hit him in the face with the wine bottle I'd bought and when he fell over I ran off. Nat was the first person I bumped into, and she was very good. Took me to her room, calmed me down, all that. We drank some of the wine, and debated whether to call the police, which was when I discovered my phone was missing. It must've fallen out of my jeans in the kerfuffle with the sex attacker. Then she noticed blood on the bottom of the bottle and said I absolutely had to stay with her.

"Turns out it was good advice. The next day, I was called to see my tutor who had the police with him. They wanted to know why my phone had been found near the body of a man in the park. I was shocked that he was dead, but managed to remember to say I'd lost it earlier in the day. When they asked where I'd been at the rough time they thought he'd died, I said with Nat. Nat was called in too, and basically was my alibi. Apparently, she made it very clear that neither of us had had any intention of leaving her room all night."

Isabel raised her eyebrows again. "Next exit, by the way. Follow signs to the North Road Industrial Estate." She ran a finger along her phone. "And, did it work?"

"Seemed to. I got my phone back and wasn't ever in the frame for the guy's murder."

"Technically manslaughter, probably, Ells. Or even self-defence." Nat leaned forward between the seats. "My little story seemed like a good idea at the time: personal enough to discourage too many questions, and they were more concerned about us drinking in our rooms than sleeping together. And it's legal, unlike whacking people with wine bottles." She tapped Isabel on the shoulder. "The guy was a known petty crim, small-time dealer who liked his own product a bit too much, apparently. They assumed he'd found Ells's phone, swiped it and had then fallen over under the influence before getting rid of it. And before you ask the next good copper's question: I got rid of the bottle – the only bit of real evidence – in the nearest council recycling thing as soon as Ells could bring herself to leave me the next morning."

"You didn't exactly try hard to kick me out, Nat."

Nat chuckled. "True. I'd been wondering if you were into girls ever since that pub crawl in Freshers' Week."

Isabel fiddled with her hair while she glanced at me then at Nat, clearly equal parts embarrassed and intrigued. "Sorry to be cheeky, ma'am, but...I thought you were straight."

"I am, pretty much." She laughed. "But, you know? I was fresh out of an all-girls' school, I was familiar with the alternative. And it was first term of first year, it can be lonely when you're in a new place and don't know anyone." She laid a hand on my shoulder gently. "And what you have to understand, DS Carter, is that Dr White here was even more of a hottie back then."

Isabel glanced at me again, for a bit longer this time, and let her hair cover her face a bit to smile without Nat seeing. "Yes, ma'am." She shifted in her seat slightly, casting a long, inquisitive look at me. Suddenly, she glanced ahead. "Oh, left here, Eloise. Then right onto the estate in about 300 yards, please."

Turning left, I glanced back at Isabel, and noticed her smiling slightly. I couldn't quite read the look in her eyes, though. "You're both kind, I'm sure." I turned into the industrial estate and followed Isabel's directions to the rear of an abandoned unit. "I never told you, you were my first time with a girl, did I, Nat?"

"Really? Could've fooled me."

"Yes. So I have that to thank you for as well."

She laughed again. "Well, that night gave me a taste for sneaking around in the shadows. Which leads us back to the present day, and it turns out I've also now accidentally killed a man who was up to no good." She passed a hand across her face and sighed, then recovered herself.  "You didn't hear me say that, either of you." She tapped my shoulder again, as I turned into the parking area behind one of the units. "So now we're quits, Ells. Anyway, this is where I leave you." She squeezed my shoulder. "Thanks again. See you again soonish, I hope, we'll have that drink. I need to borrow DS Carter for a sec." She and Isabel jumped out. Nat was transferred to another car and Isabel had a brief conversation with the driver, before Nat was whisked away.

*

After she climbed back into my passenger seat, Isabel sat for a moment and rubbed her face.

"Are you all right?"

She nodded and recovered herself. "Just the adrenalin catching up with me. I should introduce myself properly." She pulled out a police ID and let me examine it. Apparently she was indeed Detective Sergeant Isabel Carter.

"At least you use your real name. Unlike Nat." I handed the leather warrant wallet back. "So you're genuinely also the police. Even if you were running away from them back at the hotel. Nat too?"

She nodded, and smiled. "She's a Detective Inspector." She pointed vaguely back the way we'd come in. "We need to get to the local nick. I have to debrief, and there's someone there who can talk to you about it all."

"OK." I released the handbrake with a sigh. "Tell me where we're going."

*

I spent an hour or two with a very polite Detective Superintendent, who besides keeping me supplied with tea and biscuits explained that Nat – Detective Inspector Simpson, as he insisted on calling her – had been undercover for a while with a major gang in the area, and had found herself in a position to get close to the kingpin. So much so that they'd begun a relationship and contemplated marriage. Nat's superiors had decided that the wedding would be an excellent opportunity to bust the ring open. It was very unfortunate that I'd become involved; of course Eastern Counties Police Service were very grateful for my contribution, they would make sure my effects were retrieved from the hotel and returned, etc. etc., and by the way please could I sign this document to promise I wouldn't say anything until ECPS gave me permission? Thank you so much, very understanding, much appreciated...more tea, Dr White?

As I was released back into the real world, and made my way down the steps of the Police Headquarters to my car, Isabel pushed herself off the wall where she'd apparently been waiting and fell into step with me. "Did the Super explain?"

"In a fashion. I'm still not sure how I came to be involved. Apart from owing Nat one."

"None of us are, to be honest, it wasn't supposed to end like that. You were something she kept to herself until the last minute, as her own sort of backup plan. She only told me and Gary about it yesterday." She nudged my elbow with hers. "You'll have to ask her when she's out of hiding. She's in a safe house at the moment, and will be for a while, until we know the extent of the aftermath." We drew level with the car. Isabel hovered. "I know this is cheeky after all that's happened, but can I have a lift? My car's at the hotel, and I live the other side of town."

"Is that why you were hanging around? Waiting for a lift?"

"Partly. I mean, yeah, I was waiting for you." She glanced at me sideways. "To see you were OK, of course. But, also, yeah...you know..."

I stared at her for a second, unsure what to make of her. Then I thought what the hell, and laughed. "Hop in. It'll be nice to do something that feels normal, like giving a stranger a lift in a town I don't know."

*

We sat in the car outside Isabel's block of flats. She fiddled with her key. "What're you going to do now?"

I shrugged. I felt deflated now the adrenalin had worn off, and suppressed a yawn. "Go home, I suppose. The wedding seems to be off, I can't go back to the hotel for my stuff, the few days' stay there I'd planned isn't possible..."

Isabel asked where home was and, when I told her, pulled a face. "That's miles away. I didn't realise you'd come so far."

"It took me three hours to get here. At my normal speed, not your speed." I smiled. "So it's not too bad."

She smiled back. "Even so." She patted her pockets. "Oh, here. The boss insisted." She pulled out fifty quid in notes and slipped it into my handbag. Then she shifted in the seat to face me better, looking at my face carefully. "You're tired." She suppressed a sudden yawn herself. "As am I, apparently. It's been a long day. Are you hungry?"

I realised I hadn't eaten since breakfast – I'd been expecting a slap-up meal at the reception, of course, and it was now almost 5 o'clock in the evening. "Actually, now you mention it, I'm starving."

"Me too." She hesitated, then spoke in a rush without looking at me. "Say no by all means, but do you want to go out and get something? There's a couple of nice places round here that do walk-ins, and it'd be a shame to waste that gorgeous dress." She gestured down me quickly, and caught my eye suddenly. Her wide-eyed nervousness was a surprising change from the unflappable receptionist act. "Don't know about you, but I could murder a drink, too." She pointed a thumb out of the window. "Stay here tonight and go home when you feel fresher."

I wasn't sure how to respond, because if she was just being friendly and helpful, I'd rather leave things there and drive away. While I was trying to read her expression, I yawned again.

She smiled and gently put her hand on my arm. "That settles it. I wouldn't be comfortable letting you drive home tired and hungry."

"Wouldn't that be, I don't know, unprofessional or something? Making friends with someone involved in the case? Potential witness, or whatever." The pressure of her hand on my arm was nice, though.

She moved her hand up and stroked my upper arm through my jacket. "I've had my debrief, I was only drafted in to help things go smoothly. I'm off duty now, and I've been given a week's leave. So I figure who I choose to go out with tonight is my own business." She brushed some of her hair back from her face and held the ends against her neck. "Or bring back to my flat, for that matter." She waited a moment, but when I failed to make my mind up, let her hand drop from my arm. Her hand lightly brushed mine on the gearstick, then she rested it on her thigh. "OK, never mind, Forget I asked." She reached for the door handle. "Thanks, though. For the lift, but also for allowing yourself to be involved."

I caught her wrist as she started to get out. "Isabel, wait." She half-turned back, and somehow the insides of our wrists touched. I felt a little thrill, and I think she did too. I rubbed my thumb quickly over the back of her hand, and she smiled quickly, lips parted. She raised a questioning eyebrow, and I squeezed her arm lightly. "That would be nice, thanks. So, yes. To the going out, and coming back to your flat afterwards."

We gazed into each other's eyes for a second, to make sure we were both talking about the same thing. We were. She grinned. "Good. I'm looking forward to more gossip from the DI's student days." She leant in and kissed me quickly on the lips, taking me by surprise. "I'm just going to pop up and change my jacket, then there's a nice little Italian round the corner. Once we're done there, we can have an early night and you can tell me more about this famous alibi of yours."

"Tell you?"

"All right, then. Show me." She kissed me again. "See you in a sec."

**

That was about a year ago.

The operation resulted in several court cases, and ECPS told me that once they were in the public domain I didn't have to keep completely silent about being there, although they'd appreciate my continued discretion. So, in this account, I've changed the names and kept some details vague.

My stuff was released a week or so later, and having to drive back over and collect it gave me an excuse to see Isabel again. In fact, I ended up staying with her for a day or two, and what had been a lovely (but all-too-brief) one-night stand the first time, quickly – and to our mutual surprise – became something much deeper and more beautiful.

I've been going over most weekends ever since, and when she has leave, she comes and stays with me.

Nat eventually re-emerged from hiding, and she and I have picked up our friendship now that my relationship with Isabel means I'm around more.

A month ago, a job at the university near where Isabel lives came up; I applied and have just found out I've been appointed. Isabel and I have booked a few days to celebrate, in the hotel where it all began – she's made damn sure we've been given Room 120. We fully intend to be far too busy testing the bed to try climbing out of the window.