'So, what makes you think you're being haunted, Joe?' Conor paused as his eyes were drawn to the unopened cola can in front of him. It had started juddering.

Everyone watched in amazement as it slid across the dining table and came to an abrupt halt in front of Liam.

'Well, that sort of thing, for a start.'

As his brother knelt down to check under the table for magnets, Liam picked up the can and performed a cursory examination. Then he shrugged, opened it and took a drink.

'How long has it been going on?' enquired Becky.

'A couple of months.' Joe glanced up at the clock. 'My mum is due home from work soon, but if she asks, you're just my friends from school, OK? Don't mention anything about ghosts.'

Becky looked surprised. 'Your mum doesn't know that the house is haunted?'

'Nope, and I want it to stay that way. It'll only scare her and her nerves are bad enough without throwing a ghost into the mix.'

Becky looked out of the window. Joe's father, Mr Davies, was sitting on the bench in the garden. He was still in his dressing gown, even though it was late afternoon. He had a book in his hand, but was gazing off into space. 'What about your dad, does he know?'

'I don't think he notices much of anything anymore.' Joe seemed both upset and angry. 'Anyway, the weird stuff only seems to happen to me.'

Liam took a huge swig from the can and let out an almighty burp. 'We won't mention your ghost, don't worry.'

Conor looked puzzled. 'How are we going to set up our cameras without your parents noticing?'

'I've told them we're all in film club together at school. Mum knows I'm into making videos and stuff, so she thinks we're using the house as a set to make a horror short for our project.'

'Film club?' Liam raised an eyebrow. 'Cool. I didn't even know there was a film club at school.'

'There isn't, but my mum and dad don't know that.'

'And by saying we're making a horror film, it'll help explain anything strange that happens.' Becky smiled. 'That's clever.'

Joe blushed. 'Thanks.'

Liam nodded at the patio doors. 'I think your cat wants to go out.'

'He's my grandfather's cat.' Joe stood up and walked over to open the door for the mewling moggy. 'We inherited him, along with the house.'

He watched the cat padding along the garden path. 'The poor thing always heads for exactly the same spot under the rose bush. He scratches around and sleeps out there for hours, even in the rain. I think it's because he misses Grandad.'

'Was the house haunted when your grandfather lived here?' asked Becky.

'I don't know. He never mentioned anything and I certainly didn't experience anything until after we moved in.'

'So it all started after he died?' she probed.

'Well, yes, but you don't think the ghost is my grandfather, surely? He'd never try to scare me like this.'

'I'm not suggesting anything. I'm just gathering the facts. We need to know as much as possible about what's going on.

'It'll help our investigation,' agreed Conor. 'So, tell us more. What sort of things have happened?'

'Doors slamming, things moving around on their own, that sort of stuff. I put my clothes on the bed a few days ago and went for a shower. When I came back they were gone.' Joe pointed down the garden. 'I found them outside, strewn down the garden path. All except for my socks. I haven't located them yet.'

'The sock monster will have got them,' muttered Liam. 'It happens at our house all the time.'

'Nobody else could have moved them?'

Joe looked directly at Conor. 'Why would they want to?'

'I don't know, but we have to eliminate any natural causes before we defer to the supernatural. Was your mum or dad home at the time?'

'Yes, Dad was here, but he wouldn't have done that. He barely does anything anymore.' Joe sighed. 'Anyway, back to you guys. You're quite famous at school these days. I heard about what happened with Mrs Tinker, so I got Becky's number from my cousin and I texted, to see if you can help. What is it you call yourselves, the Spectre Detectors?'

'Actually, we didn't call ourselves that.' Conor frowned. 'Some journalist did. We think it sounds naff.'

'What do you call yourselves then?'

'We haven't thought of a name yet.'

'If our cases keep involving people from school, we could call ourselves Ghoul School.' Becky chuckled. 'Now that would be truly naff.'

Liam had been strolling round the room, looking at the family photographs on the walls, but he'd stopped at the one of a distinguished looking elderly couple. The man had a big curly moustache. 'Were these your grandparents? Is this your grandfather?'

'Yes, that's Grandad Alfie. We were really close. I'm sure he'd never haunt me, if that's what you're still thinking.'

'Well whoever it is, I'm fairly sure we have another poltergeist on our hands.'

His empty cola can flew off the table and hit the wall.

'Yep.' Becky turned to her cousins. 'That definitely wasn't caused by air in the pipes.'

'Or a farting dog,' joked Liam.

'Doesn't this sort of stuff scare you?'

'That's exactly why we do it,' replied Conor. 'Because it scares the hell out of us.'

'You see, something happened to the three of us a while back.' Liam sat down on the sofa. 'So we decided to start investigating the paranormal, but from a scientific viewpoint. Hopefully one day, it'll explain a few things.'

'Einstein said that energy cannot be created or destroyed,' continued Becky, 'it can only be changed. What if ghosts are simply that, energy, left behind after the body has died? Maybe the energy sticks around for a reason, or it is simply unaware that it can move on and turn into something, or someone, new. That's where we come in. We try to help with that. Even though, as my cousin has already admitted, the whole idea of ghosts scares the hell out of us.'

Liam made a fake coughing noise.

Everyone looked up to see Joe's mother standing in the doorway.

'Hi Mum, I didn't hear you come in.' Joe leapt to his feet and relieved her of her shopping bag. 'We've been talking about ghosts, because that's the theme we've decided on for the horror short we're making for film club.'

'Thanks for letting us use your lovely house to stage it, Mrs Davies.'

'Oh that's alright.' Joe's mum's tone was friendly, but there was a weariness in her voice. 'Don't I know your face from somewhere?'

The boys all glanced at each other, hoping she hadn't read the Spectre Detector article in the local newspaper.

Mrs Davies thought for a moment. 'Isn't your name Rebecca?'

'Yes, but most people call me Becky. We've met before actually, at the supermarket. You and my mum were in school together.'

'Ah, yes, that must be it. So, you're in year eleven, with Joe?'

Becky nodded. 'Liam's in our year too.'

Liam gave her a little wave from the sofa.

'I'm in the lower sixth,' asserted Conor. 'I'm a kind of technical advisor on this project. Is it alright if we start setting up our cameras now, please?'

'Yes, you go ahead. I'll just go and make some dinner.'

'Don't worry about feeding us, Mum. We'll get some pizzas in later.'

'But they're so expensive.'

'I meant frozen supermarket pizzas, they don't cost too much, and I've got the money I was paid for walking the neighbours' dogs, so don't worry.'

'Well, if you're sure.' Her smile quickly turned into a yawn. 'Oh, I'm so sorry. I'm just a bit tired, that's all. It's been another long day. Anyway, I'll go and make dinner for your dad and me and then we'll be off to bed, out of your way.'

'Is she OK?' enquired Becky. 'She doesn't seem the same as she was when I met her before.'

'She's not the same.' Joe gazed out of the window at his father, who was still seated on the garden bench. 'None of us are. It's been a tough year.'

'What time is it?' Conor looked over at his brother and frowned. 'Are you still eating?'

'You said you didn't want any more.' Liam leaned back on the sofa to dodge the cushion Conor had thrown at him.

'Yes, but you must have eaten two whole pizzas to yourself.'

'Don't mind them,' Becky whispered to Joe, 'they're always bickering.'

'It's fine. I like them.'

'So, tell me more.' She pulled her chair in closer to the dining table. 'You said your father changed after he inherited the house from your grandfather?'

'He was upset about Grandad dying. Of course he was, he'd lost his dad. But otherwise he seemed fine, at first. He was the one who suggested moving in here. He was really enthusiastic actually. Our old house was rented you see. Also, this one is closer to school and Dad's office and it has an extra bedroom too. It seemed to make sense.'

'So what happened?' Liam was kneeling up on the sofa peering over its back into the dining area. 'Your dad looked pretty spaced out earlier. Do you think he's been possessed?'

'Liam!'

'It's alright Becky, it's a fair question under the circumstances, but I genuinely think it's more a case of depression than possession. You see, my dad lost his mother last year and his father just six months later. Then he persuaded Mum that they should get a mortgage for this place and soon after they did, he lost his job.'

'But I thought he'd inherited the house.' Conor knelt up next to his brother. 'Why did they need a mortgage?'

'Inheritance tax,' spat Joe. 'Grandad paid taxes all his life, he'd already been taxed on every single penny of the hard-earned income he'd used to buy this place, but the government still demanded their forty percent when he left it to my dad. So, my parents had to borrow the money in order to pay it.'

'I thought inheritance tax was for rich people with huge estates.' Liam glanced around. 'I'm not being funny, this is a nice house and all, but it's a 3 bedroom semi in Surrey, not a country mansion.'

'I know, but it was the only way my parents would ever own their own home, so they took the plunge. Then, just two weeks later, Dad was made redundant and hasn't been able to get another job yet. He's been wandering around in his pyjamas for over a month now. He barely even speaks anymore.'

'Your mum works though, right?' Becky sounded genuinely concerned.

'Yes, and she works really hard, but she doesn't earn enough to pay for everything. It was Dad's wages they were relying on to pay the mortgage. Now it looks like we're going to lose the whole lot. All thanks to the bloody government and their taxes!'

'So why call us in?'

Becky shot Liam a dirty look. 'What?'

'Well, if they're not going to be living here anyway, why would he care if it's haunted?'

'Because Mum said we'll be better off selling it than having it repossessed. It's going on the market next week.'

'And selling a haunted house might prove tricky.' Becky squeezed his hand. 'We'll sort this for you, don't worry.'

'And there'll be no charge,' added Conor.

'But...'

Becky shot Liam a look that instantly silenced him.

'No charge,' she affirmed.

The lights flickered and then went off.

'I guess that means it's party time.' Liam looked down at his phone. 'The sensor in the upstairs hallway has just triggered.'

'Maybe it's one of my parents.' Joe jumped up off the sofa and felt around for the light switch on the wall next to him. 'I can hear footsteps. Someone's coming downstairs.'

Becky switched on her torch and trained it on the door.

'Why aren't the lights working?' cried Joe.

'It's OK,' Becky reassured him, 'electrical interference is quite normal during ghost manifestations. Energy, remember?'

The footsteps were slow, but seemed to echo throughout the entire house.

'The EMF is going crazy.' Conor looked up from the instrument in his hand and his eyes followed the torchlight towards the darkened doorway. 'Has this ever happened before?'

'No.' Joe's voice sounded tight with fear. 'But like I said, it's probably Mum or Dad.'

Liam shook his head. 'The whole house is reverberating with each footstep, so unless your mum or dad has put on a ton of weight since they went to bed, I'm pretty sure it's not them.'

'The ghost box is dead.' Becky groaned. 'I had a feeling there was a problem with it when we tested it earlier.'

Liam plucked the EVP off the sideboard and switched it on. 'I'm speaking to the spirit who is approaching us now. Tell us who you are.'

The gadget crackled, but there were no discernible words.

'Tell us your name.'

The wooden staircase creaked and groaned as the footsteps continued their descent.

Suddenly, there was a spine-tingling wail.

'What the hell was that?' Liam looked around for the source of the new sound. 'It didn't come through the EVP.'

'It's just the cat,' whispered Joe. 'He wants to be let back in.'

'Oh.' Liam's relief was short lived as a voice came over the device in his hand. He looked at the others. 'What did that voice just say? Did it say, Zuul? I've seen the original Ghostbusters film and if that voice just told us its name is Zuul, I'm out of here.'

'I'm not sure.' Conor looked at Becky's torchlit face. 'Did it say Zuul?'

'It said Zeus.' Joe sounded shocked.

'Zeus?' Liam frowned. 'So that thing is claiming to be a Greek god now?'

Conor glanced at his phone. 'The downstairs sensors have just triggered. It's arrived in the hallway and it's heading in our direction.'

'Zeus is my Grandad's cat,' stammered Joe.

'Oh come on, Joe. I mean, we deal in some pretty screwed up stuff, that's true, but there is no way that a cat can talk to us over the EVP.'

'You don't understand, Liam. The voice on the EVP, that was my grandfather.'

'You said he wouldn't haunt you.' Conor glanced back at the patio doors. 'And why would he say his cat's name?'

'Maybe he's sick of it going out there scratching up the soil and peeing on his roses?' suggested Liam.

'Shhh!' Becky's smoke-like breath was drifting around in the torchlight. The temperature in the room had suddenly dropped dramatically. 'The footsteps. They're in here with us.'

Everyone shivered.

The panes of glass in the wall hung photos started making strange crackling noises.

Becky shone her torch at them.

One after the other, icy frost was forming on their surfaces as the invisible entity passed them by.

'It's Alfie Davies, right?' Liam's eyes were firmly on the EVP. 'What do you want from your grandson, Mr Davies?'

'It must be something pretty important to scare him like this,' added Becky.

'Grandad?'

The EVP crackled again. 'Zeus.'

Everyone jumped when the patio doors flew wide open.

The cat instantly stopped crying. It was just outside the open doors and although it was completely shrouded in darkness, it's eyes were visible in the reflected light from the torch.

Becky moved closer to the door, to illuminate the cat better.

It was gazing upwards, purring.

'It looks like Zeus can see something that we can't.' Conor and the others huddled around Becky as the cat turned and calmly padded back down the garden path.

Joe tried to steady his shaking hand to keep his video camera focused.

'It's alright,' whispered Becky, 'this is your grandfather's energy, you heard his voice for yourself. You told me there's no way he would ever do anything to hurt you, so that means you're totally safe.'

'I hope you're filming this too, bro.' Liam glanced at his brother as they stepped outside the doors. 'There are footprints appearing in the grass.'

'Of course I'm filming it.' Conor zoomed in on the flattened areas of grass as they all followed the cat down the path. 'But what is Mr Davies trying to tell us?'

'Grandad's roses!' gasped Joe.

Liam observed the flowering bush. 'What about them?'

Conor paused. 'Since when do roses open at night?'

'Since when do roses bloom in February?' breathed Becky.

'They don't,' agreed Joe. 'That bush was completely bare earlier. There wasn't a single flower on it. No, Zeus don't do that. Grandad wouldn't want you to dig there.'

'Or maybe that's exactly what he does want.' Conor knelt down and started digging with his hands.

'What is it? What have you found?'

Conor plucked something from the earth. 'Are these your missing socks?'

Joe nodded. 'Why would Grandad throw my clothes all down the garden path and bury my socks?'

Liam clicked his fingers. 'Maybe he was hinting that you should get some Odour Eaters.'

'Or maybe he was trying to lead you to something.' Becky shone the light on the damp earth. 'Keep digging, Conor.'

Joe knelt down beside him and the others watched in silence as they both continued to dig.

'You're right, Becks,' cried Conor. 'I can feel something down there. It's cold and hard.'

Becky adjusted the angle of the torch again.

Joe gazed up at her. 'It looks like the lid of some sort of box.'

'It's a biscuit tin.' Liam frowned. 'Why would your grandfather bury his biscuits?'

'He wouldn't.' Joe helped Conor pull the tin out of the tightly packed earth.

They both brushed the loose soil off its rusted surface.

'I think it should be you who opens it,' said Conor.

'Well, that's another successful case under our belts.' Liam's grin faded when Lucy waved from the other side of the school yard. 'Oh great, here comes your girlfriend. What a treat.'

'Has anyone heard from Joe?' enquired Conor.

'Yes,' Becky nodded. 'He's confirmed that there have been no more spooky goings on at his house, so I think his grandfather must have moved on.'

'At least the rest of his family don't have to move on anymore.' Conor pecked Lucy on the cheek as she slipped her arm around his waist. 'Not after finding all that money in the tin.'

'Yes, they can pay all their bills and his dad is getting help for depression.' Becky beamed at her cousins. 'Things are finally looking up for them. Joe is ever so grateful for our help. He's just having a couple of days off school, to give his mum a hand with things. I think they all need a bit of time to recover, after everything that's happened. '

'That sounds like an awful lot of information to give you in a text.' Lucy eyed Becky for a reaction.

'We met for coffee actually.' Becky's cheeks flushed. 'Not that it's any of your business.'

Conor and Liam exchanged surprised glances.

'Actually, talking of business, I've got a new case for you.' Lucy held up a piece of paper and accessorised it with a smug, pearly white smile.

'One of your vacuous friends heard about the tin of money we helped find, have they?' Liam knitted his eyebrows. 'Because we're not in the treasure hunting business, Lucy.'

Even Conor looked dubious. 'It does involve a ghost, doesn't it, Luce?'

'Absolutely not.' She paused for effect. 'This one sounds far more scary than any of your silly ghosts.'