The other girls in Artemis' dormitory had been almost as relieved as she was to see Fergus safe and sound and no longer sleeping. To celebrate his clean bill of health, Penny missed an Astronomy club meeting, Rowan took a break from the library, and Tonks broke into the kitchens and stole some milk for Fergus and an array of puddings for the girls. The four of them spent an evening eating the puddings and playing games in the dormitory, until Jane Court interrupted their fun, telling them that they were making far too much noise.
"Spoilsport," said Tonks, rolling her eyes and packing away the Exploding Snap cards.
Artemis finished her slice of Bakewell tart, and stowed another away on her bookshelf to eat the next day.
"Penny," she said, trying to sound as casual as possible, "you don't happen to have the rest of that calming draught, do you?"
"Yes, it's in my sock drawer," said Penny, climbing into bed. "I was thinking of giving it to Ben. He might need it at some point."
"Yes, he might," Artemis nodded. Keeping her voice breezy, she added, "I could take it to him for you, if you like."
Penny, Tonks and Rowan all stared at her, frowning.
"What?" She asked them.
"Artemis," said Rowan, shaking her head. "You're really not a great liar, are you?"
"I don't know what you mean, Rowan."
"Right," Rowan grinned. "So you aren't planning on using the rest of that calming draught on Mrs Norris?"
"You are?" Tonks said, raising her eyebrows. "Artemis, I've got say, I'm impressed."
"Wait, why are you giving a calming draught to Mrs Norris?" Penny asked.
Artemis sighed, and shot a reproachful look at Rowan, who shrugged. She told Penny and Tonks all about the fifth floor corridor.
"So," Rowan said, once Artemis had finished, "you have the calming draught to keep Mrs Norris out of your way, but what about Filch?"
"I hadn't thought that far ahead yet," said Artemis.
"Ah, don't you worry," Tonks said. "You leave Filch to me."
"To us, you mean," Penny corrected her. "I want to help."
"You do?" Artemis asked, and both Tonks and Penny nodded emphatically. "That's great, but it has to be a secret. No one else can know, just us and Ben."
"We need a plan," said Rowan, and she opened the drawer of her bedside table, reached in, and pulled out a quill and notebook. "I'll do it now."
"Rowan, it's bedtime."
"I'm a night owl," she said, and she started to scribble. "Trust me, by breakfast, I'll have something sorted for us."
The next morning, over breakfast, Artemis and her friends discussed their plan to break into the locked room in the forbidden corridor on the fifth floor.
"I am going to give Mrs Norris the rest of Penny's calming solution," Rowan told them all. "Professor Kettleburn said to Artemis that it will make cats sleep for an hour or two, which should definitely be enough time to open that door and take a look around."
"Ben, you should unlock the door," said Artemis.
"Why me?" Ben asked, his eyes wide.
"Because, Ben, you're the best at the unlocking charm. Much better than me."
"But I don't even want to go through the door!" Ben protested. "Not if what's behind it might be cursed, like you said."
"You don't have to go through the door if you don't want to," Artemis said. "If you'd prefer, you can stay outside and keep watch while Rowan and I take a look."
"Keep watch for what?"
"Filch," said Rowan. "The teachers. The prefects. Merula Snyde."
Ben shuddered, looking over his shoulder in the direction of the Slytherin table, where Merula was sitting between a girl with glasses so large and round that they made her look almost like an insect, and a lank-haired, sallow-skinned girl who could have been Professor Snape's long-lost daughter.
"Don't look so scared, Ben," Penny smiled. "Tonks and I are going to make sure that the teachers and Mr Filch stay well out of the way."
"How?"
"Rowan's got a plan for that, too."
"Well, I was thinking that the last Quidditch match of the year is on the second-to-last Saturday in May," Rowan said. "The whole school will be watching, even the teachers. We just need to make sure Mr Filch is there, too."
"Something tells me that Filch probably isn't a big Quidditch fan," said Artemis. "He's not a fan of much, is he? I guess you'll need to make a big mess for him to clear up."
"Exactly," Rowan nodded. "Professor Sprout has a Mimbulus Mimbletonia in Greenhouse Five. They make this horrible smelling liquid called Stinksap. If Penny keeps Sprout busy, Tonks can go in and take the plant and put it somewhere in the stands..."
"Or, even better," Tonks sniggered, "the Gryffindor changing rooms."
"Yes, there will do," said Rowan, and Ben made a face. "It will make a mess that Filch will have to clean up, and that will keep him busy while the teachers are watching the game."
"See, Ben?" Artemis said. "It will all be fine."
Ben sighed, but nodded his head.
"Okay, I'll help you sneak past that door," he said. "But only because you're my friend, Artemis."
"I'm so proud of all of you," said Tonks, grinning from ear to ear. "You're all giving me a run for my money. You know, I'm going to have to really up my game if I want to keep my reputation as the troublemaker of our year."
The penultimate Saturday of May came around quicker than expected. At breakfast, Penny walked over to Professor Sprout at the teacher's table.
"Professor Sprout, I have a few questions about the homework you set on Thursday," Artemis heard her say.
"Wish me luck," said Tonks, winking at Artemis and Rowan as she rose from her seat at the Hufflepuff table.
Artemis watched Tonks walk out of the Great Hall, and beckoned Ben over from the Gryffindor table.
"Are you still happy to help us?" She asked him. He looked very pale and nervous. "It's okay if you don't want to."
"I wouldn't say I'm happy," Ben said, "but I do want to help you. You helped me with flying and with Merula, so it's only fair."
"Thank you, Ben," Artemis smiled. "The Quidditch match starts at around eleven, so once everyone goes out to the stands, we'll meet you at the Grand Staircase."
So, at eleven o'clock, while the rest of the school was waiting in the Quidditch stands, Artemis, Rowan and Ben were walking up to the fifth floor of the castle.
"Is it just me," said Rowan, shivering, "or is it cold up here?"
Artemis nodded. It was cold on the fifth floor. She'd never noticed that before. As they turned the corner and entered the forbidden corridor, it got even colder. By the time they got to the locked door, all three of them were wishing they'd worn jumpers.
It wasn't long before Mrs Norris approached them, her red eyes full of malice. .
"I really hope this works," said Rowan, pouring Penny's calming draught onto the floor in front of the cat, her hands shaking.
The three of them watched with baited breath, as Mrs Norris sniffed the calming draught suspiciously, her tail pointing straight up towards the ceiling. After what felt like an age, she started to lap up to potion.
"She's drinking it!"
Mrs Norris finished the potion and circled five times, before swaying slightly from side to side and dropping to the floor.
"We killed her," whispered Ben, clearly horrified. "We killed Filch's cat!"
Artemis bent down and touched Mrs Norris' back leg, feeling for a pulse.
"She's not dead, Ben," she said. "She's just sleeping. You'd better unlock the door, before she wakes up again."
"Okay," Ben said, and he pointed his wand at the door. "Alohamora!"
The lock clicked. Artemis stood up and placed her hand on the door handle. She pressed down and pushed the door, which started to open.
"Flipendo!"
Before she had a chance to finish opening the door, Artemis felt herself thrown up into the air and onto the ground. She looked up, and saw Merula Snyde standing in the corridor, her wand raised.
Merula cast the knockback jinx on Rowan and Ben, who suffered the same fate as Artemis, and stood over them, grinning maliciously.
"You know, Hexley, you're smart," said Merula, "but I'm smarter. Whilst you came up with your plan to unlock the door and get past that nasty cat, I came up with the plan to wait, and let you do the hard work for me."
"Merula, why are you even here?"
"Because," Merula replied, "I want to be the one to solve the mystery of the Cursed Vaults. And if you'll excuse me, I'm going to do just that."
With that she entered the room. Rowan turned to Artemis, her glasses askew.
"What do we do?" She asked.
"Well, I'm going in after her," Artemis said, climbing back up onto her feet. "I don't know what Merula's problem is, but this is to do with my brother. I'm not going to not find out what's there, just because of her."
"I'll come with you," said Rowan. "Just in case Merula tries to duel you again. Ben, are you still okay to stay here and keep watch?"
Ben nodded, and stood back up.
"Be careful," he whispered.
"We will," said Artemis. "Just stay here and make sure Mrs Norris stays asleep."
"And alive," Rowan added.
"And alive," Artemis agreed. "We'll shout if we need anything."
Artemis and Rowan opened the door again, and walked after Merula.
They found themselves in a small antechamber. The room was icy cold, even colder than the corridor, with walls that were covered in a dusting of frost and patches of ice. The only item in the room was a block of ice in the middle of it that was vaguely shaped like a person. Artemis looked at Rowan, and saw that she was as confused as she was. What did a half-finished ice sculpture have to do with her brother?
"Help me," said the ice sculpture. Its voice sounded familiar.
"Merula?" Artemis asked. She and Rowan walked around the ice sculpture, and saw that it wasn't a sculpture at all. Merula Snyde had been completely encased in a thick layer of ice, with only her face poking out. "What happened?"
"The ice," Merula said, her teeth chattering. "I touched it, and it spread all over me."
"The ice must be cursed," said Rowan. "Artemis, whatever you do, don't touch the ice."
"I wasn't going to," Artemis replied, though this wasn't true. Her first impulse had been to touch the glittering frost that covered the walls of the room.
"Well, don't just stand there," Merula said, angrily. "Get me out!"
Artemis nodded, and pointed her wand at Merula, but before she could do anything, Rowan pulled her wrist back, scowling at Merula.
"You want us to help you?"
"Obviously! I'm stuck!"
"Rowan, we can't leave her like this," said Artemis.
"Why not?" Rowan asked. "She'd have no problem leaving us if it were the other way around. Remember the Devil's Snare?"
"Oh, come on," said Merula. "I'm sorry about the Devil's Snare, okay? I'm really sorry."
"Are you sorry about putting Bulbadox powder in Artemis' cauldron and for bullying Ben?"
"Yes," Merula tried to nod her head, but it was frozen solid. "I'm sorry about that, too. Just help me. Please."
Rowan turned to Artemis and nodded. Artemis pointed her wand at the ice that had trapped Merula. She cast the first spell that came to mind.
"Flipendo!"
The ice that had spread over Merula started to crack. Artemis cast the knockback jinx on the ice a couple more times, and eventually, Merula was free.
"Say thank you," Rowan said to Merula, who scowled, but turned to Artemis and thanked her grudgingly.
"You're welcome, Merula," said Artemis. She looked around the room again. "Looks like there's nothing in this room except for a load of ice."
"Cursed ice," Rowan corrected her. "We should go before another one of us gets trapped in it."
Artemis nodded, and turned towards the door and reached for the handle.
"Stop!" Merula shouted, pointing at the door. "Don't touch it!"
Merula was right. A patch of ice had spread over the door, and the handle was completely covered in it.
"Oh no," said Artemis. She raised her wand and pointed it at the ice on the door, ready to cast the knockback jinx again.
"Artemis," Rowan said, tugging at her sleeve, "look, the ice!"
Ice was spreading from the back wall of the room across the floor, getting closer and closer to their feet.
"Flipendo!" Merula shouted, pointing her wand at the spreading ice. "Come on, you two. Flipendo!"
The three girls started to cast the knockback jinx at the ice, but it kept on coming towards them.
"We can't do this forever," said Artemis. "We need to get out of this room."
"Ben!" Rowan shouted. "Ben, help us!"
Artemis started to call for Ben, too, and so did Merula, and it wasn't long before they heard Ben's voice from the other side of the now completely frozen door.
"Bombarda!"
There was a loud bang, and the door exploded, sending shards of ice, singed wood and chips of stone scattering across the room. The three girls turned to the doorway, and saw Ben, standing in the middle of the hole he had blown in the wall.
The three girls ran out of the room. Rowan and Artemis threw their arms around Ben, and for a moment it looked like Merula was going to do the same, but instead she stuffed her hands into her pockets and cleared her throat.
"Er, thanks," she said, gruffly, and stalked away down the corridor.
"Wow," said Artemis, watching her walk away. "You didn't even have to threaten her that time, Rowan."
"Was that all that was in there?" Ben asked, peering into the room. "Just ice?"
"It's not just ice," Artemis said, shaking her head. "It's cursed ice. It was spreading, and trapping us."
"I told you whatever was in there was cursed!" Ben said, with a shudder that could have been from fear or from the cold. "I'm glad I stayed outside."
"It's a good job you did," said Artemis. "You saved us," she looked at the hole in the wall where the door used to be. "By the way, that was a really cool spell. Will you teach it to me one day?"
"Um, Artemis," Rowan said, pointing at the floor of the ice room, "you should take a look at this."
Artemis looked at what Rowan was pointing at. The ice on the ground had formed a sheet that covered the entire floor of the room. The sheet of ice was perfectly smooth, except for some peculiar markings that looked like they had been carved into it by a large, invisible knife. They could have been letters, but they weren't from any alphabet Artemis recognised.
"Are those runes?" She asked Rowan, who had pulled a pencil and sheet of parchment from her pocket.
"I don't know," she muttered, scribbling furiously, "but I'm going to find out!"
Artemis stared at the writing in the ice, willing it to make sense, and as she stared, she noticed that not only ice, but fog was spreading from the back wall of the room. She took a step backwards, but she wasn't quick enough. The fog engulfed her, and she couldn't see anything.
"Rowan?" She called out. "Ben?"
She couldn't see either of her friends through the mist. She took a step forward, and tripped on a step in front of her. She looked upwards, and saw a flight of stairs rising upwards. At the top of the stairs, stood a figure, enshrouded in the haze.
"Artemis," said a voice. It was the same voice she had heard in the library.
"Jacob," Artemis said, and she started to walk up the staircase towards her brother. "Jacob, I'm here!"
But, when the figure turned around, she saw that it wasn't Jacob at all. It was a suit of armour, which started to walk down the stairs towards her, raising its sword.
"Run, Artemis," said her brother's voice.
Artemis didn't need telling twice. She ran back down the stairs, away from the suit of armour, and found herself in a corridor, a Hogwarts corridor, that was covered in ice. She could hear the footsteps of the suit of armour behind her, and she ran through the corridor, finally reaching the Grand Staircase. As she looked at the familiar surroundings, she felt her stomach drop like a stone: the staircases that made up the Grand Staircases had frozen solid. The whole of Hogwarts was covered in the Cursed Ice.
"Artemis, look out!"
She turned around and looked up. The suit of armour was stood over her. It raised its sword once more...
"Artemis!"
Someone was shaking her. It was Ben.
"Artemis, you've gone all funny again," he said.
"What did you see this time?" Rowan asked her.
"Ice," Artemis said, blinking hard. "Ice everywhere, all over Hogwarts. And there was a suit of armour, with a sword, who came down these stairs and..."
She shuddered. Rowan put an arm around her.
"It's okay," she said, softly. "It's not real."
"I don't know," Artemis said, shaking her head. "It felt real."
"We should leave," said Ben. He looked more scared than she was. "Look, Mrs Norris is waking up!"
The three of them looked down at Mrs Norris. The cat was definitely stirring.
"We need to make sure no one finds out we were here," Rowan said, pointing at the hole Ben had blasted in the wall. "We aren't allowed to even be in this corridor, let alone blowing up doors and drugging Mr Filch's cat."
"I've got an idea," said Ben, picking up the empty vial of calming draught. "Follow me."
Ben led Rowan and Artemis up to the seventh floor of the castle, where he stopped opposite a tapestry on which group of four trolls in white tulle skirts were attempting to bend down and touch their own toes whilst a wizard with a pair of bloomers on his head stomped around them, waving a cane.
"We have an audience, everyone," the wizard with the cane said, seeing the three of them arrive. "Dances des Petits Cygnes, from the top. And, five, six, seven, eight..."
The trolls lined up and started to dance with their arms linked, the bloomer-hatted wizard humming a tune and counting in multiples of four. Artemis was so engrossed in watching the tapestry that she barely noticed Ben pacing in front of the facing wall, muttering to himself, until Rowan tapped her and pointed at the wall. A door had appeared just where Ben had been pacing.
"How did you do that?" She asked him.
"I don't know, really," he said. "One day I came up here to hide from Merula, and I could tell she was going to find me, and I was just looking for a place where I could go to be hidden for a while, and then this door appeared."
"What's in there?"
"What isn't in there, more like," said Ben, opening the door. "Come and see."
Artemis and Rowan followed Ben into the secret room, in which shelves stacked haphazardly with various items and artefacts rose from floor to ceiling.
"You can hide anything here," said Ben, "no one would ever find it unless they knew where to look."
He tucked the empty potion bottle down the back of a large cabinet. Rowan was examining a set of skulls on a shelf nearby.
"This place is fascinating," she said. "Why couldn't we have investigated this door from the start?"