While Jenna sat reading Chapter Thirteen, Septimus Heap, Apprentice to the ExtraOrdinary Wizard, had just been caught reading something he was not meant to have read. Marcia Overstrand, ExtraOrdinary Wizard of the Castle, had been temporarily defeated by a squabble in her kitchen between the coffeepot and the stove. In exasperation she had decided to leave them to it and go check on her Apprentice. She had found him in the Pyramid Library immersed in a pile of tattered old texts.

"What exactly do you think you are doing?" Marcia demanded.

Septimus jumped guiltily to his feet and shoved the papers under the book he should have been reading. "Nothing," he said.

"That," said Marcia sternly, "was exactly what I thought you were doing." She surveyed her Apprentice, trying - but not entirely succeeding - to keep her stern expression. Septimus had a startled look in his brilliant green eyes and his curly, straw-colored hair was tangled from the way Marcia knew he twisted it when he was concentrating. "In case it has escaped your memory," she told him, "you are meant to be reviewing for your Prediction Practical Examination tomorrow morning. Not reading a load of five-hundred-year-old drivel."

"It's not drivel," objected Septimus. "It's - "

"I know perfectly well what it is," Marcia said. "I have told you before. Alchemie is total twaddle and a complete waste of time. You may as well go boil your socks and expect them to turn into gold."

"But I'm not reading about Alchemie," protested Septimus. "It's Physik."

"Same difference," said Marcia. "It's Marcellus Pye, I presume?"

"Yes. He's really good."

"He's really irrelevant, Septimus." Marcia reached under the book Septimus had hastily placed on top - The Principles and Practice of Elementary Prediction - and drew out the sheaf of yellowed and fragile papers covered in faint jottings. "Anyway," she said, "these are only his notes."

"I know. It's a pity his book has disappeared."

"Hmm. It's time you went to bed. You've got an early start tomorrow. Seven minutes past seven and not a second later. Understand?"

Septimus nodded.

"Well, off you go then."

"But, Marcia..."

"What?"

"I'm really interested in Physik. And Marcellus did it the best. He had all sorts of medicines and cures worked out, and he knew all about why we get sick. Do you think I could learn about it?"

"No," said Marcia. "You don't need it, Septimus. Magyk can do everything that Physik can."

"It can't cure the Sickenesse though," said Septimus stubbornly.

Marcia pursed her lips. Septimus was not the first to have pointed this out. "It will," she insisted, "it will. I just have to work on it - what was that?" A loud crash came from the kitchen two floors below and Marcia shot off.

Septimus sighed. He put Marcellus's papers back in the old box he had found in a dusty corner, blew out the candle and went downstairs to bed.

Septimus did not sleep well. Every night for a week he had had the same bad dream about the exam, and this night was no exception. He dreamed that he had missed the exam, Marcia chased him, and he fell down a chimney that went on forever and ever ... He kept grabbing at the walls to stop himself but still he kept falling ... falling ... falling.

"Been having a fight with your blankets, Septimus?" A familiar voice echoed down the chimney. "Looks like you lost," the voice continued with a chuckle. "Not wise to take on a pair of blankets, lad. One, maybe, but two blankets always gang up on you. Vicious things, blankets."

Septimus forced himself out of his dream and sat up, gasping from the cold autumn air that Alther Mella had let in through the window.

"You all right?" Alther asked, concerned. The ghost settled himself down comfortably on Septimus's bed.

"Wh ... errr?" Septimus mumbled, focusing with some difficulty on the slightly transparent figure of Alther Mella, ex-ExtraOrdinary Wizard and frequent visitor to the WizardTower. Alther was not as difficult to see as some of the older ghosts in the Castle, but at nighttime his faded purple robes had a tendency to blend into the background, and the dimness of the light made it harder to see the dark brown bloodstains over the ghost's heart, which Septimus always found his eye was drawn to, however hard he tried not to look. Alther had a calm and kind expression in his old green eyes as he regarded his favorite Apprentice.

"Same bad dream?" Alther inquired.

"Um. Yes," Septimus admitted.

"Did you remember to use your Flyte Charm this time?" asked Alther.

"Er, no. Perhaps I will next time. Except I hope there isn't a next time. It's a horrible dream." Septimus shuddered and pulled one of the obstinate blankets up to his chin.

"Hmm. Well, dreams come to us for a reason. Sometimes they tell us things we need to know," mused Alther, floating up from the pillow and straightening himself out with a ghostly groan. "Now, I thought you might like a little trip down to a place I know not far from here."

Septimus yawned. "But what about Marcia?" he asked sleepily.

"Marcia's got one of her headaches," said Alther. "I don't know why she gets so upset over that contrary coffeepot. I'd get rid of it if I were her. She's gone to bed so there's no need to bother her. Anyway, we'll be back before she knows we're gone."

Septimus did not want to go back to sleep and get into the dream yet again. He tumbled out of bed and pulled on his green woolen Apprentice tunic, which was neatly folded on the end of his bed, just as he had been taught to do with his Young Army uniform every night for the first ten years of his life, and fastened his silver Apprentice belt.

"Ready?" asked Alther.

"Ready," replied Septimus. He headed for the window that Alther had Caused to open when he had arrived. Septimus climbed onto the broad wooden windowsill and stood in the open window, looking down at the precipitous drop some twenty-one floors down, something that he never would have dreamed of doing a few months ago, given his fear of heights. But now Septimus had lost his fear, and the reason for this was held tightly in his left hand - the Flyte Charm.

Septimus carefully took the small golden arrow with its delicate silver flights and held it between his right finger and thumb. "Where are we going?" he asked Alther, who was hovering in front of him and absentmindedly trying to perfect a backward flip.

"Hole in the Wall," Alther replied, upside down. "Nice place. Must have told you about it."

"But that's a tavern," objected Septimus. "I'm too young to go into taverns. And Marcia says they're dens of - "

"Oh, you mustn't take any notice of what Marcia says about taverns," Alther told him. "Marcia has some strange theory that people go to taverns just to talk about her behind her back. I've told her that people have much more interesting things than her to discuss - like the price of fish - but she won't believe it."

Alther spun around and righted himself so that he was floating in front of Septimus. The ghost looked at the slight figure standing on the windowsill, his curly hair blowing in the wind that always played around the top of the WizardTower and his green eyes flashing with Magyk, as the Flyte Charm grew warm in his grasp. Although Alther had been helping Septimus practice the Art of Flyte for three months now - ever since Septimus had found the Flyte Charm - he still felt a flash of fear when he saw the boy standing on the edge of a sheer drop.

"I'll follow you," said Septimus, his voice almost blown away by a sudden gust of wind.

"What?"

"I'll follow you, Alther. Okay?"

"Fine. I'll watch you take off first though. Just to make sure you're nice and steady."

Septimus did not object. He liked Alther being with him, and once or twice during the early days of Flyte, he had been very glad of the ghost's advice, particularly one nasty time when he had nearly crashed into the roof of the Manuscriptorium. Septimus had, in fact, been showing off to his friend Beetle, but Alther had merely Caused a sudden uplift of air and set Septimus safely down in the backyard and had not mentioned the showing-off at all.

The Flyte Charm was beginning to feel hot in Septimus's grasp. It was time to go. Taking a deep breath, Septimus hurled himself into the night. For a brief moment he felt the leaden pull of gravity dragging him toward the earth, and then the thing that he loved happened: The downward drag disappeared and he was set free, free like a bird to fly and soar, to loop and swirl through the night air, supported and held safe by the Flyte Charm. At the moment the Flyte Charm kicked in, Alther relaxed and set off in front of Septimus, arms held out like the wings of a gliding eagle, while Septimus followed more erratically, trying out his new slalom skids.

They arrived at the Hole in the Wall Tavern with a bump - or rather, Septimus did. Alther shot straight through the wall, leaving Septimus to use a slalom skid for real and land with a crash in the bushes that grew across the tumbledown entrance to the tavern.

Alther came a few minutes later to find Septimus picking himself up out of the bushes. "Sorry, Septimus," Alther apologized. "Just saw old Olaf Snorrelssen. Nice chap. Northern Trader, never got home to see his baby, you know. Sad, really. Goes on about it a bit but he's a good soul. I keep telling him he ought to get out and about the Castle, but there're not many places he can go apart from the Traders' Market and the Grateful Turbot. So he just sits here staring into his beer."

Septimus brushed a few leaves off his tunic, put the Flyte Charm back into his Apprentice belt and surveyed the entrance to the Hole in the Wall Tavern. It didn't look much like a tavern to him. It looked pretty much like a pile of stones dumped at the base of the Castle wall. There was no sign outside the door. In fact, there was no door, neither were there the usual steamy, lit windows that Septimus was used to seeing in taverns because, well, there were no windows either. As Septimus wondered whether Alther was playing some kind of complicated joke on him, a ghostly nun wafted by.

"Good evening, Alther," said the nun in her soft accent.

"Good evening, Sister Bernadette," Alther replied with a smile. The nun gave him a flirtatious wave and disappeared through the pile of stones. She was followed by a virtually see-through knight with his arm in a sling, who carefully tied up his limping horse to an invisible post and shuffled through the bush from which Septimus had just extricated himself.

"Looks like, being a busy night tonight, we've got quite a few visitors," mused Alther, nodding in a friendly fashion to the knight.

"But - they're gbosts," said Septimus.

"Well, of course they're ghosts," said Alther. "That's the whole point of the tavern. Any ghost is welcome; all others are by invitation only. And it's not easy to get an invitation, I can tell you. At least two ghosts have to invite you. Of course, we've had the odd gate-crasher over the years but it's still a pretty well-kept secret."

Three faded Ancient ExtraOrdinary Wizards had now arrived and were stuck at the entrance trying to decide who should go in first. Septimus nodded politely to them and asked Alther, "So who else has invited me?"

Alther, distracted by the sight of the three Wizards deciding to go in all at once to the accompaniment of much giggling, did not answer the question. "Come on, lad, follow me," he said, and disappeared through the wall. Some moments later, Alther reappeared and said, a little impatiently, "Come on, Septimus, best not keep Queen Etheldredda waiting."

"But I - "

"Just squeeze behind the bush and slip behind the pile of stones. You'll find the way in."

Septimus pushed through the bush, and feeling his way with the help of the light from the glowing Dragon Ring that he wore on his right index finger, he found a narrow passage' way behind the stones that took him deep into a broad, low space hidden within the Castle walls - the Hole in the Wall Tavern.

Septimus was astonished; he had never seen so many ghosts together in one place. Septimus was used to seeing ghosts around the Castle, as he had always been the sensitive kind of boy that ghosts liked to Appear to, and since he had been wearing the green robes of an Apprentice to the ExtraOrdinary Wizard, Septimus had noticed that even more ghosts chose to Appear to him. But there was something about the relaxed atmosphere in the Hole in the Wall Tavern - and the fact that he was with Alther, one of the most popular regulars - that meant most of the ghosts allowed Septimus to see them. It was an amazing sight: there were the usual ExtraOrdinary Wizard ghosts, all in purple but with many different styles of robe reflecting the fashions over the years; Septimus was used to seeing these around the Palace and the WizardTower. There were a surprising number of Queens and Princesses too. But there were other ghosts that Septimus was unused to seeing: knights and their pages, farmers and farmers' wives, sailors and traders, scribes and scholars, tramps and tinkers and all manner of Castle inhabitants from the last few thousand years, all holding on to their Hole in the Wall tankards, which they had been given on their first visit and had never needed to refill.

A quiet hum of ghostly chatter pervaded the atmosphere as conversations started many years ago continued their leisurely way, but over in a far corner a regal figure heard the hesitant footsteps of a living boy cut through the noise. She got up from her seat beside the fire and glided through the throng, a respectful sea of ghosts parting before her.

"Septimus Heap," said Queen Etheldredda. "Five and a half minutes late, but no matter. I have been waiting five hundred years. Follow me."