For the next few days half the school seemed to think that Tansy was behind the attack on Mrs Norris and the other half believed that Harry was responsible. The following Wednesday afternoon, Tansy entered the Great Hall for dinner on her own – she'd come straight from her Transfiguration class and she was starving.

'Oh look everyone! Better keep your pets under close supervision; here comes Laverstock!' Malfoy's obnoxious voice echoed round the hall, disturbing everyone who was trying to eat their dinner in peace. Tansy blushed as everyone in the vicinity turned to look at her. Heartily wishing that she had Harry's invisibility cloak, she hurried over to the Gryffindor table and sat down, pulling a plate of pasta towards her. At that moment she was joined by her friends who had come from their afternoon History of Magic class.

'Well she was helpful!' Ron snorted, as he helped himself to pasta-bake and salad.

'Who was helpful?' Tansy asked, tearing her eyes away from Malfoy, (who was imitating someone strangling a cat over at the Slytherin table).

'Moaning Myrtle of course!' Ron snorted again, 'we went to see if we could find out any clues, you know, where Mrs Norris was attacked, cause of what Professor Binns told us…' He began to eat with enthusiasm and Hermione picked up the story where he had left off.

'Professor Binns told us a few things about the Chamber of Secrets; apparently Salazar Slytherin wanted to get rid of all the Muggle-borns in the school,' Hermione pursed her lips in disagreement. 'According to the legend he left a secret chamber with a… a something; a type of monster, inside it, which he could use to purge the school of all the Muggle-born students…'

'But that's disgusting!' Tansy interrupted in horror.

'We're not disagreeing with you Tansy…' Harry said, with a frown. '…and now all this creepy stuff has started to happen at Hogwarts; first Mrs Norris then who else?' Tansy shivered as a prickle of pure fear grated down her spine.

That evening Tansy couldn't concentrate on her Transfiguration homework and, after struggling with it for over an hour, she finally slammed Intermediate Transfiguration shut. To her surprise, she had her three friends' immediate attention.

'Who can it be though? Who'd want all the Squibs and Muggle-borns out of Hogwarts?' Hermione asked quietly. Tansy swallowed saliva.

'I think that's clear Hermione,' she replied slowly. 'I've been thinking about it since he was up in the second floor corridor on Halloween with all the Gryffindors and Ravenclaws. I mean why would he be there if he didn't already know what had happened – the Slytherin common room is somewhere in the dungeons.' Hermione looked doubtfully at her best friend.

'You don't mean Malfoy?' Ron, however, nodded thoughtfully.

'He thinks all Muggle-borns are scum Hermione. And anyway, you heard him: You'll be next Mudbloods!'

'And all his family have been in Slytherin,' Harry put in thoughtfully. 'He told me that the first time I met him… in Diagon Alley before we even came to Hogwarts...' (He added when Tansy looked confused). '…the whole Malfoy family could've had the key to the Chamber of Secrets for centuries, been passing it down father to son…' Tansy giggled at Harry's imagination. Since when did the Chamber have a key?

'Yes but how do we prove it?' Ron interrupted, sounding slightly exasperated.

'There might be a way,' Hermione muttered, casting a wary glance around the room to ensure that no one else was within hearing distance. 'Of course it would be difficult and dangerous... oh... and we'd be breaking about a million school rules.'

'When you feel like explaining, will you let us know? Ron snapped, obviously irritated because he didn't know what she was talking about. Tansy, however, had a shrewd idea what Hermione meant and she looked uncomfortably at her best friend.

'She just means that we could use Polyjuice Potion to get into the Slytherin common room, don't you Hermione?' She interjected quickly, trying, rather feebly, to stop the impending argument between her two friends.

'Hang on a minute, what does this Poly-thingy do exactly?' Harry asked suspiciously.

'It transforms you into somebody else. Snape mentioned it in Potions a few weeks ago. We could change into four Slytherins and nobody would have any idea that it was us. Malfoy would probably tell us anything!' Hermione answered impatiently.

'It sounds a bit dodgy to me,' Ron said dubiously. 'We could be stuck looking like four of the Slytherins for ever…'

Hermione ignored him. 'Getting the book from the Restricted Section of the library is going to be the hardest part,' she said thoughtfully. Tansy privately agreed with her; there was only one way to get a book out of the Restricted Section and somehow she didn't think that any of the teachers would be too thrilled at the prospect of four second years borrowing a book that was evidently meant for much older students who were studying advanced Potions.

To her utmost surprise however, despite her gloomy predictions, this didn't prove to be a problem: Lockhart gave Hermione his signature without even checking which book they wanted, with a fervent comment of:

'I'm sure no one will mind me giving such an intelligent student a little bit of extra help.' (This caused Hermione to turn bright pink and also caused Ron to have an enormous choking fit as he tried to stifle a laugh with his handkerchief).

As they were getting ready for bed that evening, Hermione turned to Tansy, looking nervous. In fact, she looked terrified and Tansy was quite alarmed. She glanced down at her clothes, trying to think how best to find out what was wrong. Hermione solved this problem.

'Um Tansy, I don't think I can make the Polyjuice Potion on my own…' She said extremely quickly. Tansy looked up from her folded robes in surprise.

'But that means…' She trailed off, very much wrong-footed.

'I know, I know!' Hermione answered, wringing her hands. 'Maybe you can help me?' Tansy looked at her friend, trying, (and failing), to hide her amusement.

'Well you know I would, but come on Hermione; I'm the worst in the year at Potions!'

'No you're not!' Hermione said suddenly. 'You're actually okay, it's Snape that puts you off Potions.' Tansy shook her head in disbelief.

'I'll try my best Hermione, but it's definitely my worst subject.'

The next morning Tansy woke very suddenly as Hermione shook her by the shoulder.

'Come on, we're really late! The match starts in five minutes.' She rolled over and groaned as her friend left the room; Quidditch – why would anyone waste a Saturday on it? She swung her legs over the side of the bed but as she stood up the dormitory veered alarmingly around her and she grabbed at the hangings of her four-poster for support and shut her eyes. After a few deep breaths she opened them again but the spinning hadn't stopped. Feeling slightly alarmed, she sat down on the bed for a minute before attempting again. This time her knees gave way and she collapsed in a heap on the floor. Deciding not to bother attempting to climb back into bed, she shut her eyes and let sleep claim her again.

'Tansy! Tansy! Are you okay?' Tansy opened her eyes to see Lavender and Parvati staring down at her. Their faces seemed to be spinning round her so she shut her eyes tightly. 'We should get Professor McGonagall… she's really ill!'

'No! I'm fine,' Tansy croaked, without opening her eyes. 'I'm just a bit dizzy that's all, will you help me up onto the bed?'

'We won!' Parvati told her cheerfully as she helped Tansy lie down on her bed. 'Only Harry hurt his arm and Professor Lockhart, well he tried to mend it, only he ended up removing all the bones instead…'

'What?' Tansy opened her eyes, (and shut them again).

'He'll be fine; Ron and Hermione are with him, anyway you sure you're okay Tansy? You look terribly white…' Parvati asked, with a bite of concern in her voice. Tansy gave a tiny nod; she knew that if she didn't feel better soon then she'd ask Hermione to help her down to the hospital wing but lying down wasn't too bad and her head seemed to be spinning more slowly than before.

Much later she awoke; the dormitory was dark and three softly breathing lumps under the bedclothes on the adjacent four-poster beds indicated that they were occupied. Her head ached and she felt nauseous. She was desperate for the loo so she pushed shaky legs out of bed and tottered bare-footed out of the room, holding onto everything she could. After throwing up violently her head felt clearer and she knew that she had to get downstairs to the hospital wing – perhaps Madam Pomfrey would be able to give her something for the dizziness.

Tansy never knew how she managed to get from Gryffindor tower to the third floor. As she reached the bottom of the final staircase, she suddenly saw a long black shadow which seemed to slide around the corner and disappear. She blinked and looked around confusedly and that was when she saw the body, lying, face down, next to the wall. Head swimming, she closed her eyes hoping it was a hallucination or a vision or something, but when she opened them again the body was still there: It was Colin Creevey, an annoying Gryffindor first year who had a habit of following Harry around. Tansy took a step back, unable to decide what to do.

'Miss Laverstock! What on earth do you think you're doing?' Professor McGonagall had appeared. '…oh my goodness! What's happened to Mr Creevey?' The Professor's voice seemed to be getting louder and quieter like a badly tuned radio.

Tansy tried to focus as Professor McGonagall came towards her with swift steps but it was impossible.

Sorry Professor…' She began faintly. '...feel funny… hospital wing…' The stairwell tipped alarmingly and she slipped gratefully out of consciousness.

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