The term had ended and the Christmas holidays had begun, but Artemis didn't feel very festive. She still felt deflated after seeing how upset Charlie Weasley was about having to give up his Cruppy. Luckily, Rowan had some good news that soon lifted her mood.

"This will cheer you up," she said over their sandwiches at lunchtime. "I've decoded the first section of your brother's notebook!"

"You have? Rowan, that's amazing," Artemis gasped. "What did it say?"

"Well, firstly he makes a lot of compelling points about the connection between Boggarts and one of the Cursed Vaults," replied Rowan.

"So the Boggarts are another curse!"

"Your brother definitely thought so," Rowan said. "He was really interested in the Boggarts, he's done loads of research on them. You could probably use his notes to teach a whole Defence Against the Dark Arts lesson."

"Does he say where the Cursed Vault is?" Artemis asked her.

"No, but do you remember the book I found in the library last year? The one by the old Charms professor who was trying to find the Vaults?"

"Yes, it had all the changing maps."

"Exactly, the maps showed how Hogwarts changed over time, and what didn't change. It's the places that don't change that are important," said Rowan. "Jacob knew a lot about the immovable locations in the castle, considering half the maps are missing. Which made me think, maybe your brother took the maps from the library for his research."

"That would make sense," Artemis nodded. "Where do you think they are now, though? Maybe Madam Rosmerta has them."

"No, it's somewhere in the castle," Rowan told her. "Your brother mentions that he had taken over a secret room to do his research in."

"Where?"

"I don't know. He changes the code whenever he talks about it," Rowan said. "He changes between codes a lot, that's what made me take so long to decipher it."

Artemis tried her hardest to hide her disappointment, but Rowan knew her too well for that.

"Sorry, Artemis."

"It's okay, Rowan. I'm just happy you're helping me," she said. "And I'm impressed that you managed to decode any of it at all."

"I don't mind helping, it's all so interesting. If anything I'm enjoying myself," said Rowan, her eyes lit up behind her silver-framed glasses. Artemis couldn't help but smile at the look on her best friend's face. "Now, looking at this page about your brother's room, a lot of the code looks runic, but they're not in any script I recognise. I can keep looking, but I was thinking that Bill might have a better idea than me, seeing as he's a couple of years ahead of us."

Artemis and Rowan took the book straight to the library, where they found Bill with his head in a Defence Against the Dark Arts textbook. Rowan stood hovering behind him, and Artemis sat cross-legged on the table next to where he was working.

"I can't believe you're in here revising at Christmas," she said to him.

"Just you wait 'til you get to fifth year," Bill replied, laying down his quill and grinning at Artemis. "Come on, then. What do you want this time?"

"I want you to translate this for me," said Artemis, and she thrust Jacob's notebook under his nose. "It's directions to a room in the castle."

"It looks runic," said Rowan, "but I'm not sure about the language."

Bill frowned and took the notebook from Artemis, looking at the symbols on the pages carefully.

"That's because they aren't in any particular language," he said, after looking at the symbols for almost five whole minutes. "They're a cross between three different scripts."

"Of course," Rowan sighed, and leant over Bill's shoulder as the two of them peered at the notebook. "That's why they all looked so strangely familiar."

"Do either of you know what it means?"

"Most of it, but it doesn't make sense," said Bill.

"Really?" Rowan was looking at the runes over the top of her glasses, her nose wrinkled in concentration. "That looks like a seven, that means steps, and that means upwards. Surely if you put all that together, it means we need to go to the seventh floor."

"Definitely. That bit makes perfect sense, it gets a bit woolly after that," said Bill. "See here? We have the symbol for an opening or gateway, and this here means to be against or opposing something. You've got symbols that mean picture or painting, and cloth, and insanity. Then he's just written the word 'Barnabas', so I'd say you're looking for a doorway that is facing a tapestry of Barnabas the Barmy."

"I'm confused," said Artemis. "How is that woolly?"

"Well, I know where the tapestry of Barnabas the Barmy is on the seventh floor, and there isn't a door in that corridor."

Rowan gasped.

"Yes, there is!" she turned to Artemis. "Remember?"

"Rowan, I have no idea who Barnabas the Barmy is."

"He's the bloke who tried to teach ballet to trolls," said Bill, shaking his head. "Total nutter."

Artemis' jaw dropped.

"The Room of Hidden Things," she whispered to Rowan.

"Barnabas did say last year that the room is different for everyone who finds it," Rowan said. "It wouldn't surprise me if your brother found it, he clearly knew the secrets of the castle as well as anyone."

"Are either of you two going to tell me what in Merlin's name is going on?" Bill asked them.

"My brother was researching the Cursed Vaults in a secret room on the seventh floor," replied Artemis, and she took Jacob's notebook back from him, closed it, and handed it to Rowan. "It's opposite the tapestry of the dancing trolls, but it's... well, it's hard to explain," she jumped up, and tugged at the sleeve of Bill's jumper. "Come on, I'll show you."

"But my revision..." Bill said, looking anxiously at his pile of books and parchment. Artemis raised her eyebrows at him, and he sighed before he got up and followed her out of the library.

On the seventh floor, Artemis and Bill stopped opposite a large tapestry of a group of trolls in pink tights and leotards. A wizard holding a cane and wearing a pair of bloomers on his head strutted around the dancing trolls.

"That was abysmal," he was telling the trolls. "Now, Christmas is only a week away, so we just have six days to rehearse this. Go back to the Waltz of the Flowers, straight into the entrance of the Sugar Plum Fairy, and don't forget to smile this time..."

"Raving lunatic," Bill muttered under his breath, and he turned to grin at Artemis, who was pacing in front of the wall opposite the tapestry. "You too, Artemis Hexley. What on earth are you doing?"

"Shut up and let me concentrate," said Artemis, and she carried on pacing, and whispering, "I need to find my brother's room, I need to find my brother's room."

As she paced in front of the wall, a door appeared in it. Bill stopped smirking at Artemis, and his eyes widened.

"How did you -"

"Ben found this place in first year. Barnabas said it's called the Come-and-Go Room," she told him. "You walk here, and say what you want the room to do, and it does it for you."

"I've heard of this place before," said Bill. "The Room Of Requirement. I didn't realise it actually existed."

"Let's see what's inside," Artemis approached the door to the Come-and-Go room, but it was locked with a shiny blue and gold padlock. She took out her wand and pointed it at the lock. "Alohamora!"

Nothing happened. Bill stood next to her and bent down to look at the padlock.

"It must have an unlockable locking charm on it," he said. "You'll have to speak to the owner."

"Great," muttered Artemis, rolling her eyes. "It could belong to anyone!"

"No, it couldn't," replied Bill. "It belongs to Tulip Karasu."

"What? How could you possibly know that?"

"Because I can read," Bill laughed and pointed at the padlock. Surely enough, the lock had the name engraved into it.

"Tulip Karasu," Artemis frowned. "Hang on, I think I might know her! She's in my Transfiguration class!"

"There you go, then," said Bill, and the two of them walked back towards the library. "You managed to get all your shopping done in Hogsmeade last weekend, then?"

Artemis sighed.

"I did, but the Cruppies destroyed my gift for that present game Penny came up with," she said, then looked up at Bill in earnest. Of course, she thought, why didn't she ask him about this before? "Bill, I picked your brother's name out of Penny's tiny cauldron, and I'm pretty stuck on what to get him. Do you have any ideas?"

"Well, he's always loved -"

"Dragons, yes. So everyone keeps telling me. But I can hardly get him a dragon, can I?"

"It doesn't have to be a literal dragon, Artemis," Bill laughed and carried on walking, but Artemis stopped dead in her tracks as inspiration struck her. "He'll be happy with anything remotely to do with with dragons. Honestly, he's the easiest person in the world to..." Bill's voice tailed off as he realised that Artemis was no longer walking next to him, and he turned back to face her. "Artemis, what are you doing back there?"

"Nothing... You just gave me a brilliant idea, that's all," Artemis said, running to catch up with him.

"What?"

"You'll see. At least, you will if it works. When we get back to the library, can I borrow your quill?"

Artemis and Rowan had stayed at school for the Christmas holidays the year before to keep Ben Copper company while he was in the Hospital Wing, but she had to admit that Christmas at Hogwarts was a lot more magical with more friends around.

Over the month of December, the castle had become decorated from floor to ceiling, and outside a thick blanket of snow had fallen over the grounds. The four Hufflepuff girls had spent most mornings playing in the snow, wrapped up in their warmest clothes, and most afternoons tucked up in the common room with blankets and books and dry woollen socks. Tonks had even taught herself how to bewitch snowballs, and on Christmas Eve, she taught the others how to do it, too.

"I might bewitch them to hit Merula next," she cackled, sending snowball soaring towards Artemis, who swiftly dodged it and with a flick of her wand, sent it back to Tonks.

"Oh, don't," Penny sighed. "She's the only Slytherin in our year staying for the holidays. It must be awful, being all alone at Christmas without any friends."

"She'd have more friends if she was nicer to people."

"I know, but I can't help feeling sorry for her. Maybe we should ask her to sit with us at Christmas lunch tomorrow."

"We could," Rowan said, halfway through making a sculpture out of snow that looked somewhat like a Sphinx, "but she won't have a present."

"It looks like Charlie might not, either," muttered Artemis.

"Your great idea didn't go to plan, then?"

"Not yet. There's still time for a last minute miracle, I guess."

"Why don't you just wrap up some of the stuff we got from Filch's office?" Tonks suggested.

"But that's your stuff!"

"Not really. There was loads extra and you paid half for the frisbees, so technically half the loot is yours."

At this point the girls were joined by the Weasley brothers, who Tonks and Artemis greeted by sending a flurry of enchanted snowballs in their direction. Chaos quickly ensued, as the two boys retaliated with a volley of snowballs aimed at the Hufflepuffs. In the corner of her eye, Artemis spotted Merula Snyde watching the scene, her violet eyes wide, and she felt a distinct pang of sympathy.

The girls returned to their common room damp with now-melted snow, and found that it had been covered from top to bottom with garlands of holly, ivy, and mistletoe. Tiny lights flickered all around the room and stockings hung over the fireplace. In one corner, a small but perfectly conical Christmas tree stood on a low table.

"It looks beautiful!" Penny exclaimed, pressing her hands to her mouth.

Artemis fetched Fergus the cat, a packet of cards, and the spare bag of Zonko's goods from the dormitory.

"Sorry, Cruppies," she said to Scully and Toto. "I just don't trust you not to eat the Christmas decorations."

Artemis picked out a screaming yo-yo and packet of sugar quills to wrap up for Charlie, and opened another packet of sugar quills to share with her friends as they played Exploding Snap until midnight, while Fergus played on the floor with a string of tinsel.

The next morning, a rotund man with a large white beard shook Artemis awake. He looked like a cross between Professor Dumbledore and Hagrid. Startled, she leapt out of bed and grabbed her wand to defend herself. The man laughed loudly. She would have recognised the laugh anywhere.

"Tonks! You nearly gave me a heart attack!"

"Ho Ho Ho!" the bearded man with the exact same laugh as Tonks sniggered. "Merry Christmas, Artemis."

"It wouldn't have been very merry for you if I'd jinxed you," Artemis replied, hugging Tonks as her features returned to normal.

Once Penny and Rowan were up, the four girls went into the common room to find four piles of presents. Artemis had received some Muggle sweets from Ben Copper, a tiny barrel of Butterbeer from Madam Rosmerta, and a box of rock cakes from Hagrid.

Her mother, who was spending Christmas with Aunt Tina and Uncle Newt, had sent her a fleece-lined jacket, which, she realised when she put it on, she'd have to grow into, and her Great-Aunt and Uncle had sent her a pair of sturdy lace-up boots that would be perfect for exploring the countryside looking for creatures next time she visited them. They had also slid a letter into the wrapping paper. She read the letter carefully, a smile stretching across her face as she did so.

"What's in the letter?" Rowan asked, as she opened a stationery kit with a fancy peacock feather quill from one of her relatives. "Looks like it's good news."

"It's great news, but I can't tell you what it is, it will ruin the surprise. You wouldn't happen to have a spare envelope, would you?"

The girls had agreed to meet the Weasley brothers in the Great Hall for Christmas lunch. When they arrived, they found them wearing matching knitted jumpers with their initials on.

"Merry Christmas, lads," Tonks said as she sat down next to Bill. "You should have told us there was a dress code. I'd have worn my jumper, too."

Christmas lunch at Hogwarts was a feast like no other; the food was excellent, the crackers filled with real hats and live mice, and, most importantly, the company better than any Artemis had ever shared a Christmas with before. Once the main meal was over, she and her friends sat around a flaming Christmas pudding that none of them could yet bring themselves to eat.

"I'm so full, I might burst," said Rowan.

"Please don't, it sounds messy," Artemis grinned at her.

"Why don't we do our presents now and have pudding after?" Bill suggested. "That way we might actually have room to eat something else."

The others concurred, but Artemis saw Penny's blue eyes drift away from the table. She followed the line of their gaze, and realised that Penny was staring sadly at Merula. Merula was sitting alone at the Slytherin table, and Artemis felt lonely just looking at her.

"Is it just me," whispered Charlie, who had noticed Artemis and Penny watching Merula eat her dinner by herself, "or do you two feel bad for her as well?"

"You know what will make you feel better?" Tonks asked. "Presents."

Artemis smiled, but she couldn't pull her eyes away from the Slytherin table.

"Just wait a minute," she said to her friends, and walked over to where Merula sat.

"What do you want, Hexley?" said Merula, scowling up at her.

"I wanted to see if you'd like to come over to our table for pudding."

"Why?" Merula eyed her suspiciously. "We aren't friends."

"No, we're not," Artemis agreed. "But it's Christmas. You don't honestly want to sit here by yourself, do you?"

Merula didn't reply. Artemis shrugged.

"Fine. Suit yourself, then. But you're welcome to join us if you change your mind."

"At least you tried," Penny smiled at her as she returned to the table. She clapped her hands and beamed at the others. "So, who's going to go first?"

Tonks went first, and gave Rowan the book Artemis had recommended for her. Next, Rowan gave Bill the book about Ancient Mesopotamian curses that they had seen on the shelves in Tomes and Scrolls, and then Penny handed Tonks a box containing some more Zonko's products.

"I'm ever so sorry if you have any of this already," she said. "I just didn't know if you were going to get all your belongings back from Filch or not."

"Don't be silly, Penny, I always love having more Zonko's goodies," Tonks rummaged in the box, inspecting its contents. "Yes! Frog Spawn Soap!"

Next, Penny opened her gift from Charlie: a leather potions belt, almost identical to the ones Artemis had seen in the windows at Dervish and Banges, although the design wasn't quite as intricate.

"Wow, Charlie!" Penny gasped as she examined the belt. "I've been wanting one of these since the first Hogsmeade trip. But really, you shouldn't have! They're so frightfully expensive."

"They are, so I got the leather from Hagrid and made one myself," Charlie shrugged. "I'm afraid that means it's not nearly as fancy as the ones from Dervish and Banges, though."

"Oh, no," said Penny, so pleased that she looked positively radiant. "If anything it makes it even more special."

"That is really impressive, Charlie," Bill said as he leant across the table to admire his brother's handiwork. "Makes me feel a bit bad, actually. I got mum to make this one for you, Artemis."

Artemis opened the gift Bill handed her. Inside was grey and yellow knitted jumper with a large black and white Hufflepuff badger on the front. Artemis' eyes lit up, and she immediately took off the jumper she was already wearing and put on the new one, much to the amusement of Bill.

"Well, I did remember you saying how much you liked mine," he said, laughing at the delighted expression on Artemis' face.

"You know, mum must really like you," Charlie said. "She only usually puts in that much effort for family members."

"Well, Artemis has always known how to make quite an impression." Tonks gave a knowing grin, making Rowan choke on her mulled pumpkin juice.

"Er, is it okay if I sit here?" a small voice said. Six faces turned up to see Merula Snyde standing over them, her face flushed and anxious looking.

"Absolutely!" said Penny brightly, shuffling towards Artemis to make space for the newcomer. "Charlie, Artemis, move up."

"We're just opening presents, Merula. This one's for you, here," Artemis passed her the Zonko's items she'd wrapped for Charlie the night before, Rowan and Tonks shooting her confused looks from across the table. Merula looked even more confused, but she took the gift, somewhat grudgingly thanked Artemis, and unwrapped it. Reaching into her pocket, Artemis drew out an envelope and handed it to Charlie. "Scully ate your original present, Charlie, so I'm afraid I had to get some help from my family, too."

Charlie took the envelope, opened it and unfolded the parchment within. His face was unreadable as his brown eyes scanned the sheet of parchment, and as they reached the bottom, they flicked back to the top and started to scan again, his eyebrows knitting together as he did so.

Artemis looked at her friends, all watching the scene unfold in a silence that was quickly becoming awkward. She frowned. Perhaps her great idea hadn't been so great after all.

"I mean, there are more Zonko's products back in my dormitory," she said quickly. "I can run back and get them for you if -"

Suddenly, all the air was knocked out of Artemis' body. Still clutching the parchment, Charlie had thrown his arms around her and hugged her so tightly she could hardly breathe.

"Bloody hell, Charlie," Bill said, looking both alarmed and entertained. "Be careful with her, she's only small!"

Seeming to realise the force with which he'd flung himself at her her, Charlie let go of Artemis instantly, his cheeks turning almost as red as his hair.

"What does it say? We've been waiting all week to find out what Artemis has been plotting."

"It's... it's a letter from Artemis's aunt and uncle in Dorset. They're going to adopt Dragon for me," Charlie explained. "so that he won't have to go to strangers, and I... I can go and visit him."

"Like I said, feel free to help yourself to any of the Zonko's stuff if you want a proper present as well," said Artemis.

"No," Charlie looked directly at her and blinked slowly. He shook his head. "No, I don't... This is... It's... Thank you."

"You're welcome."

"Ugh, that's just great," said a sarcastic voice, and everyone turned to see Merula rolling her eyes. "Now I look like a right prat for not getting anyone anything."

"You don't need to get anyone anything," Penny smiled at her. "It's just lovely that you're here with us."

"Liz and Barnaby told me you can do a pretty cool spell where you make a mini flurry of snow," Charlie said, having composed himself somewhat. "Maybe you could teach us how you do it? That would be a great gift."

Merula frowned for a second, then slowly nodded in agreement.

"Fine, I'll teach you all the snow spell. But I want pudding first."

The rest of the Christmas holidays flew by in a blur of snowball fights and Cruppy walks, of playing boardgames and eating cheese. It wasn't long before the decorations vanished and the Cruppies were sent to their new homes.

The night before the start of the new term, Artemis and the other Hufflepuff girls sat in the dormitory, eating the last of the sugar quills, whilst Fergus, contented by the departure of Scully and Bones, lay belly-up on the floor in the middle of the room, purring loudly.

"How much do you want to bet that Merula will be back to her usual vile self once the rest of the Slytherins are back?" Tonks asked.

"I don't think she'll be half as mean," Penny, ever the optimist, replied. "You know, she's not that bad, really. It's almost like she's our friend, now."

"Almost," Rowan muttered darkly, looking at Penny over the top of her book.

It was true that Merula had been noticeably less unpleasant during the Christmas holidays. After Artemis had invited her to join her friends at Christmas lunch, Merula had taught them all a spell to create snowflakes without complaining or belittling any of them. She had even thanked Artemis later in the day for including her in the fun.

"You're welcome, Merula," Artemis had replied to her. "We didn't want you to be left out. Especially not at Christmas."

"Well, it means a lot," Merula said, looking down at her leather lace up boots. "It's actually been the nicest Christmas I've had since... well, since I stopped living with my parents."

Artemis didn't say anything. She had been told that Merula's parents were Death Eaters who had been sent to the wizard prison Azkaban, but she didn't know whether or not this was true. It could have just been one of the many rumours that circulated around the school.

"You know, it was my mum who taught me how to make the snowflake spell," Merula continued. "She used to cast it for me every year at Christmas, until..."

Her voice tailed off. Artemis placed a hand on her forearm.

"It's hard, isn't it? Missing people at Christmas," she said, kindly. "I know how you feel. To be honest with you, this has been the best Christmas I've had in a while, too."

Merula pulled her arm away from Artemis quickly, like she had been burnt.

"Yeah, well, anyway," she sniffed, backing away from Artemis. "I mean, we don't have to talk about it. It's not like we're friends. Merry Christmas, Hexley."

With that, she had skulked away, leaving Artemis to return the festive greeting to the back of her head.

"Sorry, Penny," Artemis stopped reminiscing and turned to her friend, "but I'm with Tonks and Rowan. Somehow, I doubt that Merula will want to have anything to do with us once the new term starts."