As it turned out, Hermione did, indeed, have an angelic singing voice. Harry was almost as mesmerised by it as Fluffy was, as his best friend sang the enormous dog - and all three of its heads - into a soporific slumber.

* "The Owl and the Pussy-cat went to sea

In a beautiful pea-green boat,

They took some honey, and plenty of money,

Wrapped up in a five-pound note." *

(*copyright Edward Lear, The Random House Book of Poetry for Children (1983)*)

Harry listened open-mouthed as Hermione sang, sounding as much like the divine as Harry could ever conceive. He was a little cross that she'd never demonstrated just how beautiful her voice was, and he wondered if he could purloin her into singing him some Weird Sisters songs if he asked her to. That was a request for later, though. For now, he just stared at her, until she pointed angrily to the trap door and sent Harry back to task.

"Oh, right. Sorry," Harry muttered, hurrying forwards and tugging open the heavy leaden door.

It was very dark inside. It wasn't a sheer drop, as Harry had wildly expected, but a set of crude steps roughly hewn from the rock and soil. Harry couldn't see through the darkness to where the steps might lead. He was held fast by the prospect of the thick gloom ahead, but then Hermione's words echoed in his mind.

I will be your light.

And he took power from that greater than anything Harry had ever known. It was just the dark, and he had the strongest light just behind him, protecting him.

There was nothing to be afraid of ... not while Hermione was near.

So he marched forward with his new courage as a sort of Hermione-shaped battering ram. It drove back the shadows, made them cower into the crevices of the tunnel as Harry hurried along it. There was a growl from behind, as Hermione stopped singing and jogged up to Harry's side. He stopped in the dark to wait for her.

"Pretty song," he quipped. "What made you come up with that?"

"I'm not sure," Hermione confessed, as she drew her wand and whispered lumos.

Harry huffed. "Now why didn't I think of that?"

Hermione laughed under the flickering wand-light. "I do the thinking, you do the feeling in this partnership."

"So what were you thinking, when you picked that lullaby? It was very nice ... and you do sing like a ... well ... something that sings really prettily."

Harry didn't want to call her an angel. There wasn't a grain of dishonesty in the name, but he was suddenly painfully shy of saying something like that. He didn't know what she might think if he did, and the risk of her running back up the tunnel just wasn't worth it right now.

"Thank you, Harry!" Hermione gushed under her wand. "And, well, I just had a sudden thought about hoping Hedwig and Pap were okay - an owl and a pussycat, you know - and the poem just came to me. But I made up the melody myself."

"Well, it was very good."

"Thanks! But don't ask me to sing it again, because I wont!"

"Spoilsport," Harry smirked. "Come on, let's see what we come up against first."

A minute later, and Harry wished he hadn't asked.

"What in the name of Merlin is this!" Harry cried.

For they were looking at a long corridor, equally as rugged as the stairway they'd been steadily descending. They were a long way under the school now, and the smell of damp and vegetation was almost overpowering. By the light of Hermione's wand they could see the entire corridor criss-crossed by thick vines or ...

"Cobwebs?" Harry wavered, drawing his wand in case a herd of Acromantula suddenly stampeded towards them.

"No, they aren't cobwebs, Harry!" Hermione whispered lowly. "These are the tendrils of a plant. And if I'm not mistaken ... stand back!"

"Devil's Snare!" Harry yelped, as Hermione sent a jet of bluebell flames at a tendril that had snaked its way around Harry's calf. They stepped back to consider the situation.

"Lumos!" Hermione cast again, this time using her other wand. By the light of the two powerful beams, they could see all the way along the corridor ... and the tangled mass facing them.

"How are we supposed to get through that?" Harry moaned, casting his eyes over the lattice-like barrier blocking their path ahead.

"What does Devil's Snare dislike?" Hermione pressed, as though giving Harry a snap quiz on his homework.

"Heat and light!" Harry cried. "But ... I cant do that fire spell you can."

"Of course you can," Hermione chirped brightly. "Are you a potter, or not? They are the original masters of fire, coming even before blacksmiths. A potter who cant make fire! What a nonsense notion! I'll teach you the spell, it's easy."

And so she did. The incantation was incendio, and the wand movement a curvy little twist, and soon Harry was sending jets of fire from his wand that were quite as potent as Hermione's, only they were emerald green rather than bluebell in colour.

"That's great, Harry!" Hermione sang. "I really think you've gotten the hang of it. Ready?"

"Ready," Harry announced firmly, brandishing his wand like a swordsman of old.

Then Hermione darted forwards. The Devil's Snare snapped out viciously at her, like the jaws of a many-headed hydra. She did her best to flick her bluebell flames at as many of the sharp-thorned creepers as she could, but Harry still heard her yelp every few seconds as one broke through and pierced the thin cotton of her Hogwarts robes.

The sound stirred Harry to action. He tucked up into her slipstream, angling his green fire at any of the streaking tendrils that Hermione's eagle-eye missed. Together, they battled through yard-by-yard, until eventually the evil plant simply gave up and slithered back to the darkness, as Hermione and Harry inadvertently combined their brother wands in a joint spell so powerful that it actually incinerated many of the arms of the Snare as it reached out for them one last time.

"Are you okay?" Harry asked, as they raced clear into a plant-free part of the corridor beyond. He was keen to make sure she wasn't hurt.

"I'm fine," Hermione replied, recasting lumos to light their way ahead. "A few scratches, but I'll live. You?"

"I'm a bit ashamed that you did more of the work and outscored me, but I'm sure I'll get a chance to even things up!" Harry guffawed. "I don't like to lose!"

"And you're friends with me?" Hermione laughed. "Good luck with that!"

"Just lead on," Harry quirked, pushing Hermione playfully along the dark corridor before them.

The passageway sloped downwards now, and the only sound was the dripping of water from the walls. They could be miles under the school at this point, way under the plumbing. Harry hoped that was water dripping on his head, and not the collated waste of a thousand empty bladders from the students high above. He dry retched as another drop splashed onto the lens of his glasses. Up ahead they could hear a sort of rushing sound, maybe a whispering of sorts.

"Do you think it's ghosts?" Hermione hushed in a shuddering voice.

"Could be," Harry muttered. "Do you know how to kill a ghost?"

"No. Do you?"

"If I ever did, I've forgotten," Harry confessed, shivering in his damp robes. "You know, I think it sounds more like flapping ... maybe wings."

And he was right. From a chamber at the end of the corridor, with a ceiling so vaulted any of the great cathedrals of Europe would be proud of it, the source of the sound was revealed. They looked like hundreds of little birds, but as one attacked Hermione - when she stepped boldly into the brightly lit room - she caught it and showed it to Harry.

"It's not a little birdie, but a little key, look!" she hummed, in a very un-Hermione-ish sing-song voice, as she thrust the key into Harry's hand. "Ooh, Harry! Do you think there's a king key somewhere? And do you think he's really rude! You know ... kinky? Geddit? King-Key! Ha ha ha."

Then Hermione started giggling uncontrollably and grabbed onto the front of Harry's robes, nearly dragging him to the floor as she, herself, fell to one knee in her mirth.

"Hermione!" Harry cried in concern. "Are you okay?"

"Yesh, yesh I'm fine," Hermione replied, somewhat drunkenly. "But are you sure you're okay? Has your skin always been this elastic and pully? It looks weird!"

And with that she reached up and began pulling at Harry's cheeks, as though trying to stretch his skin around his head.

"Oi! Stop that!" Harry reprimanded, pulling Hermione's hands away from his now raw flesh.

"Okay, I will," Hermione huffed. "Ooh, look, there's a broom here, Harry. I wonder why."

She tapped her fingers to her chin as she thought, as the other hand rhythmically rapped Harry over the head with the tail-twig end of the broom she'd picked up.

"Will you stop!" Harry hissed. "Why are you being so mental?"

"I think those keys are drugged, you know," Hermione pondered in that strangely babyish voice. "I reckon if I run out they will all go for me. Then we'll know."

Before Harry had any sort of time to protest, Hermione dashed away from him and into the heart of the chamber. As she'd predicted, the mass of keys shot directly at her, pecking her with sharp little nips. Harry's first instinct was to race to her aid, but then he looked up at the clear air above him.

And there, suspended high above, was a key far bigger, chunkier and grander than than any of the others. A true King of the Keys. Harry laughed along with Hermione, who sounded like she was being tickled to within an inch of her life by the other keys.

Grabbing the broom Hermione had been hitting him with, Harry kicked off from the ground and shot upwards like a dart. The key saw him coming and tried to flutter away. Not for nothing, though, was Harry a Quidditch Seeker, and after a brief chase he closed his fist around the thick brass object. He raced back to the door on the other side of the chamber and jammed the struggling key into the lock, damaging its wings in the process.

"Yes!" Harry cried as the door clicked open and the now battered key flew back up towards the ceiling.

After bracing the door with his wand, Harry rushed over to Hermione and started swatting the other keys away from her with his broom. When he had cleared a path to his best friend, he reached down and scooped her up. She was delicately light, and Harry found he could quite easily carry her away from the keys and across the chamber towards safety.

"Ooh, Harry!" Hermione teased saucily, as Harry stepped through the open doorway. "Carrying me across the threshold already! Aren't we supposed to have a few dates first!?"

Hermione giggled insanely hard at that, and curled a balled fist into that bit of Harry's robe that she could reach, while her other arm squeezed tight around his neck where she was clinging onto him. Harry blushed madly and tried to ignore Hermione's playfulness, placing her gently down onto the rutted ground and reaching for his wand from under the door, which slammed shut as soon as it was free.

The fresh air of the corridor seemed to sober Hermione up in an instant. She stood quickly and straightened out her robes, before clearing her throat and speaking in an oddly high-pitched octave.

"Good job," she said in a false tone. "Shall we see what comes next?"

"Yes, lets," Harry agreed enthusiastically, then followed as Hermione led the way into the next chamber.

And right onto the chequered floor of a giant chessboard.

"I assume we have to play our way across," Harry mused, as Hermione inspected the enormous chessmen.

"I agree," she nodded. "It makes sense alchemically, too."

"How so?" Harry quizzed.

"Well, right now we are in the black stage," Hermione explained. "Meaning you are a Black King. In order to progress, you have to become a white king, presumably by beating the one standing on the opposite side of the board."

The huge chess piece in question turned his expressionless head towards Harry in a clear gesture of challenge.

And Harry accepted at once.

"Fine. I'll be the Black King," Harry announced, watching as the offending piece turned and walked away from the board, leaving Harry free to stand on its vacant square. "But what about you? What will you be?"

"Well, I have to be the most powerful and most influential of your allies in real life," Hermione replied with a shy blush. "So ... I think I'd better be your queen."

The inference wasn't lost on Harry, who felt a nervous flutter cross his chest. But in the same instance he realised how glad he was that Hermione was there with him right now. If anyone was to be his queen, he rather thought he'd like it to be her. That meant something else, something important, he wasn't insensible of that fact. Harry decided he'd try and work out what it was later as a matter of urgency ... assuming the giant chess game didn't smash his tiny head to smithereens.

But Hermione was good at this. Smart and clever, and with a tactical eye she'd not revealed before, she played the best game of chess Hogwarts had ever seen, decimating the opposition both in the direction of her troops and in how many enemy pieces she took care of herself. Before long, the enemy king was standing alone, and Hermione herself was the one who moved forwards to make the final checkmate.

The white king took off his crown ... and threw it at Harry's feet.

"You did it!" Harry whooped in triumph. "You won!"

"No, we won!" Hermione corrected with a victorious smile. "Come on my white king. Four tasks down, three to go."

"What can we expect this time?" Harry asked joining Hermione in the adjoining passageway.

"Well, the first stage is always associated with fire," Hermione began. "Then we had earth with the Snare, air with the flying keys, and the chess game was a mental task, which is generally considered a water association."

"So what comes after that? This fifth element you mentioned?"

"No, this is where the alchemist begins looking internally in the Opus," Hermione explained lowly. "We are leaving the earthly, Lower Work and looking at the Higher Work. It will be dealing with the final dark aspects of the psyche to achieve enlightenment, and then testing that growth with a challenge to the higher mind."

"You'd better do that one then!" Harry smirked. "I don't think I have a higher mind. But what will I face, I wonder."

"You will face me."

Harry stopped, and looked into the gloom. And his breath left his lungs in a stinging rush. For there, blocking their path, was a powerful, black-maned lion!

"Oh my!" Hermione squeaked in shock. "Harry! Be careful."

"Who are you!" Harry hissed. "Or what are you?"

For Harry couldn't shake a sense of familiarity as he looked at the massive paws and powerful body. He didn't like the sensation, for there was a dark malice behind the eyes of the beast now stalking towards them.

"I am Mercurius, I am your anger, you rage, your internal drive," the lion replied. "I am the part of you that hopes your friends fail, and that you succeed in their place. I AM you!"

"Dont believe him, Harry!" Hermione whispered. "It isn't true!"

But Harry barely heard her. The lion's voice was deep and lyrical, hypnotic even, and laced with layers of meaning that Harry understood on what he could only describe as a psychic level. There was a definite sense of truth in his words, no matter how hard they were for Harry to hear. For a moment, he wondered if he was seeing ... his own dæmon! But he hoped he wasn't. For he hated to think that this was the real him, his actual soul. But if it was ... who was he to argue with it?

"Yes, you understand, don't you?" Mercurius purred, brushing his snout against Harry's hand. "I am the part of you that enjoys seeing your friends be less than you, the part that knows how superior you are to them. I am the power that you hold inside, the part that will lead you to rule the world! Forget this girl, come with me and let us be great together!"

For a moment, Harry was sorely tempted. He was almost about to move forwards, when Hermione suddenly stepped in front of him.

And when she spoke, her voice had become a blend of her own ... and that of her own dæmon.

"You mustn't believe this, Harry," Hermione told him firmly, her voice flickering between tones. "If it were true, do you think I would have allowed it? Allowed you to touch me so intimately? To touch me in parts I should never have permitted you to? No, Harry, I would never have let you, if I'd sensed such darkness in you. I'd have never let you touch me ... here."

And she reached out her hand, to splay her digits against Harry's chest ... and the essence of Papageno flowed right inside ... to Harry's real dæmon.

And Harry lost all his senses in a rush of gorgeous, breathless emotion. It was as if his very soul was set afire with divine passion and inspiration.

It was overpowering. It sent Harry to his knees, and brought euphoric tears to his eyes. He struggled to get a clean gulp of air, to revel in whatever this empowerment was that was running through him. But the sensation was flowing away like the details of a beautiful dream, now that Hermione was no longer touching his heart. He clutched helplessly at his chest, as though trying to hold the feeling in, but it was drifting away fast like a Spring mist.

And in its place it left anger, for the residue of the Dark Temptation that Harry was so nearly taken by ... and he directed all of it at the foul beast still prowling around the corridor ... at his own very real demon.

Harry raised his wand, but Hermione stepped close again, drawing her own phoenix wand and pressing it to his.

"Together?" she asked with a beautiful smile.

"On three!" Harry agreed, grinning back.

And three seconds later the most powerful incendio spell ever cast at Hogwarts incinerated whatever it was in front of them. A quick fist pump later and they were facing the next chamber.

They stepped into a perfectly circular room and immediately a fire sprang up both in front and behind of them. The one ahead was covered in black flame, the one behind purple. They were trapped. In the middle of the room was a long table with different-shaped potion bottles on it, and a riddle on how to work out what was in each.

"My turn," Hermione chirped brightly. "It's a puzzle! This should be fun."

"If you take longer than three minutes to solve it you owe me a box of chocolate frogs!" Harry funned, sitting down to watch Hermione work.

She worked the puzzle out in less than two.

"This tiny thing," Hermione announced, holding up the smallest bottle. "Will get you through the black fire. That fat one on the end will get me back through the other one."

"Then ... you really aren't coming with me?" Harry asked in a quavering voice.

"No, Harry ... you have to go on ... alone."

For the first time since they'd opened the door on the Third Floor corridor, Harry felt truly afraid.

Hermione bit her lip, and Harry could tell she was trying to be brave ...