grabbing Harry's shoulder.

They froze, watching. Harry could just see the outline of something huge and curved, lying right across the tunnel. It wasn't moving.

'Maybe it's asleep,' he breathed, glancing back at the other two. Lockhart's hands were pressed over his eyes. Harry turned back to look at the thing, his heart beating so fast it hurt.

Very slowly, his eyes as narrow as he could make them and still see, Harry edged forward, his wand held high.

The light slid over a gigantic snake skin, of a vivid, poisonous green, lying curled and empty across the tunnel floor. The creature that had shed it must have been twenty feet long at least.

'Blimey,' said Ron weakly.

'Neat,' sickly using her pocket knife, Amelia cut a bit of the skin off and put it in her pocket. 'Never know what magic power this thing could have,'

There was a sudden movement behind them. Gilderoy Lockhart's knees had given way.

'Get up,' said Ron sharply, pointing his wand at Lockhart.

Lockhart got to his feet - then he dived at Ron, knocking him to the ground.

Harry jumped forward, but too late. Lockhart was straightening up, panting, Ron's wand in his hand and a gleaming smile back on his face.

'Can I kill him now?' asked Amelia to Harry.

'The adventure ends here!' he said. 'I shall take a bit of this skin back up to the school, tell them I was too late to save the girl, and that you three tragically lost your minds at the sight of her mangled body. Say goodbye to your memories!'

He raised Ron's Spellotaped wand high over his head and yelled, 'Obliviate!'

The wand exploded with the force of a small bomb. Amelia scammed and scrambled out of the way of falling rocks tripping over herself. Harry flung his arms over his head and ran, slipping over the coils of snake skin, out of the way of great chunks of tunnel ceiling which were thundering to the floor. Next moment, he was standing alone, gazing at a solid wall of broken rock.

'Ron!' he shouted. 'Are you OK? Ron!'

'Ron! Ron! I swear to god, if you are dead, I will bring you back to life and kill you!' screamed Amelia.

'I'm here!' came Ron's muffled voice from behind the rockfall. 'I'm OK. This git's not, though – he got blasted by the wand.'

'Ha'! laughed Amelia. 'Isn't karma sweet!'

There was a dull thud and a loud 'ow!'. It sounded as though Ron had just kicked Lockhart in the shins.

'What now?' Ron's voice said, sounding desperate. 'We can't get through. It'll take ages ...'

Harry looked up at the tunnel ceiling. Huge cracks had