Harry, Ron and Hermione were so deep in conversation about what Harry had overheard Snape talking about to Dumbledore the previous evening that they walked into the classroom without noticing who was sitting behind the desk, or that the others weren't quite so unobservant.

'Ouch, Neville! Get a move on!' Ron had just walked into the thunderstruck Neville. Hermione saw immediately why he had stopped so suddenly.

'Professor Lupin!'

Harry and Ron turned around and their jaws simultaneously dropped. Sitting calmly with a secretive smile on his face was Remus Lupin.

'Good afternoon, class. Sorry I couldn't be here for the start of term, but I had other business to attend to. Professor Dumbledore asked me to fill in until a permanent teacher is arranged. Come on, sit down.'

The whole class was still standing as if rooted to the spot. Slowly the spell broke and a huge cheer ripped through the stone room, causing Lupin to flush to the roots of his hair. Dumbledore had been a good teacher, but they all had thought that Remus was the best DADA teacher they had ever had.

The lesson proceeded much as it had when Lupin had taught before, with much good humour and enjoyment, 'Right, today we're starting on Dark groups and organisations. You've got to know which weirdo's are out there. Can anyone name any?' A few hands shot straight into the air, Harmiones included, 'Miss Patil?'

'The Death Eaters.'

'Yes, the most conspicuous and violent of our time. However they have so much history that I'm going to devote a whole lesson to them next time. Anyone else? Mr Longbottom?'

Neville's voice shook as it always did when answering a question, 'The Sons of the Serpent?'

'Yes, well done, Neville. This is the group which it is thought originally gave rise to You Know Who and the Death Eaters. A very select little set, this one. Their only entry criteria was that the members had to be able to speak Parselmouth. This, as you know, is a very rare gift.

'This faction seemed bent on world domination and snake-worship. Luckily they never got too far, but a breakaway member of the Serpent's, known to us today as Lord Voldemort, appears to have got them a step further to their goal.'

Most people flinched at Lupin's blatant use of the feared name.

'Any others? Harry?'

'The Lupuscan Circle?'

'Now that's a really obscure one, where did you hear about them?'

'I just heard the name somewhere.'

'Yes, the Lupuscan Circle, also known as the Goldeneyes or the Wannabe Werewolves.' Most of the class looked at him incredulously when he said this.

Hermione's hand shot straight back up into the air, 'You mean people who actually want to be werewolves?'

'That's exactly what I mean, Miss Granger, although I don't understand why. Take it from someone who knows, it's not pleasant. It is said that the Circle revere wolves of all kinds, and that werewolves in their transformed state can recognise a Lupuscan and will not harm them. Little of their practises are known and many do not believe that such a cult exists. Many places have been cited as the birthplace and home of the Circle, including this castle, but I think we can safely discount it.'

Lupin continued in this vein, telling them about various odd groups and sects, each with their own strange rituals and aims. But at odd intervals, strange howling noises came drifting through the open window.

'What's that?' Ron murmured out of the corner of his mouth to Harry.

Harry shrugged but Hermione answered, not looking up from the notes she was taking, 'Phil Collins, Dance Into The Light.'

'What?'

'Listen, can't you? Harry, you must know what I'm talking about.'

'Well done, Miss Granger. Five points to Gryffindor for that superb interpretation of a howled version of Phil Collins's 'Dance into the Light'. Deciphering howls isn't that easy. Who is that?'

'It's Storm, the runaway rith.'

'Think of that, two werewolves with a love of Muggle music in one place. Still, I like a bit of background noise.'

Harry could almost hear the words through the howls now, although if Hermione hadn't told him he'd never have guessed. Aunt Petunia liked singing along to the radio, though at least the rith was howling tunefully unlike his aunt's painful screeches. Ron was none the wiser, never having spent much time with Muggles or listening to their music.

The rith's repertoire continued with, 'Truly, Madly, Deeply', 'China In Your Hands', 'I'll Be There For You', 'This Kiss', a particularly heartrending version of 'Too Much Love Will Kill You' and was halfway through 'Girls Just Wanna Have Fun' when it was cut short by a dull thud and a sharp yelp. Someone was obviously not as impressed by her singing talents as Lupin and had Banished something large and heavy in her direction, halting the impromptu concert.

'Pity,' Lupin mused, 'Right that's it for today, people. I want one roll of parchment on a Dark Order of your choice in for next Tuesday.'

The class all left talking nineteen-to-the-dozen except for the trio who hung back a while. Professor Lupin was packing his books into a briefcase that looked considerably more worn and battered since its last outing at Hogwarts.

'It's good to see you three again. Surprised to see me again, eh?'

'Well, yeah, Sirius never said anything about it.'

'Ah, Sirius, I really should drop him an owl. He was staying with me, you see. I said I was taking a walk to clear my head and think about things and I ended up here. I started out three weeks ago. Still, these things happen, don't they?'

'But I thought you weren't coming back.'

'Strange story, Mr Weasley. I left because of all those complaint letters from parents. However, after I had gone Dumbledore was surprised how many more he received from parents and students alike saying how well I taught and how having a werewolf for a teacher was an excellent idea, as long as I was contained during the change, seeing as how I'd have practical experience of the arts without being a servant of You Know Who. I've only got you lot to thank, really. I never knew how popular I was.'

'That's great, Professor.'

'Please, call me Remus, at least when we're alone. We're friends, aren't we?'

The door flew open and in walked Professor Snape, 'Professor Dumbledore, I have.' Snape's face froze in an expression of shock and hatred.

'Good afternoon, Severus, what a pleasure it is to see you again.'

'Remus, what are you doing here?'

'Professor Dumbledore reinstated my position as Defence Against the Dark Arts teacher. Wonderful, isn't it?'

'Yes, quite.' If there was ever any evidence of people saying one thing but meaning quite another then this was it. Snape bit off the end of his words so that they were said with utter revulsion.

'Miss Granger, Mr Potter and Mr Weasley were just welcoming me back. It's nice to feel wanted isn't it? Was there anything, Severus?'

With a snarl aimed at all four, Snape stormed out slamming the door behind him. Immediately the four within dissolved into helpless laughter.

'Did you see his face?'

'His jaw was so clamped together I thought he was going to break it!'

'You could almost hear his teeth grinding!