'STUPEFY!'

'Quick – Professor, over here …'

'He needs help –'

'Bring him inside, Miss Chang; Davies, you go, too.'

'CONFRINGO!'

Spells exploded above our heads and I ducked to avoid a stray curse. The Battle of Hogwarts had begun, and Lord Voldemort and his army of Death Eaters and dark creatures were laying siege to the castle. Already, the shield of protective enchantments cast by the teachers had been shaken and mostly destroyed. From my position on the wide battlements that ringed Ravenclaw Tower, I could see the battle unfolding in the dark grounds far below. Professor Flitwick had led a group of us up the tower as part of the battle strategy devised by the Order of the Phoenix, but no one had anticipated that our position would come under such heavy fire so early on. Behind my back, the imposing shape of the familiar tower was pockmarked with small craters, and most of the glass in the towering mullioned windows had been shattered.

'All right, lads, prepare yourselves for a fresh assault!' cried Professor Flitwick from the front of the battlements. 'I want all wands directed at those giants heading towards the greenhouses – they cannot be allowed to reach the castle walls!'

I rose from my crouch and made eye contact with Stephen, who was standing stock still with his wand already pointed towards the grounds. His face was streaked with dust and blood. He gave me a curt nod, his jaw set. Kevin clasped my shoulder as he stood up, brushing off a fresh powdering of debris that had showered from the tower's roof. As I took my position between them, I could see spells flying from the Gryffindor and Astronomy towers, which were also being utilised for the defence of the school.

'FIRE!' roared Professor Flitwick.

With my wand pointed over the parapet, I took aim and cried, 'EXPULSO!'

My cry was echoed on all sides, and nearly two dozen streaks of silver light erupted from the tower, hurtling down into the grounds. I could hear the agonised roar of the giants as our spells found their marks. Stephen bellowed in triumph as we saw one of the smaller giants stagger and fall, its head crushing the front half of the nearest greenhouse. As I revelled in the small victory, I noticed something odd in the sky above the Forbidden Forest.

I leaned forwards and squinted at the black clouds. There was something hurtling through the air towards the school. In fact, it looked like several somethings. My eyes widened as I realised what it was.

'Professor!' I cried, gesturing with my wand. 'We've got a crowd of Death Eaters on broomsticks heading this way!'

Professor Flitwick cast a cold eye against the clouds and made a small noise of discontent. He hopped down from the small stone platform at the front of the battlements and started issuing orders.

'Brace yourselves. We have a squadron of flying enemies heading in our direction. Wands at the ready! Clear the east flank of the battlements – I want wands concentrated on the west!'

Glancing over my shoulder, I saw Cho Chang clambering through the ruined window to take a glance. Roger Davies stood at her shoulder.

'We'll cast protective spells from the common room, Professor,' she said at once.

Professor Flitwick nodded curtly.

'Very good.'

I hastened along with Stephen and Kevin to the west side of the battlements, keeping the approaching brooms in sight. At that moment there was a sudden explosion that rocked the entire school, and a huge burst of flame erupted from the dark form of the Quidditch stadium. Dancing tongues of fire spat from the Hogwarts banners draped over the wooden stands, casting a flickering illumination across the grounds.

The dozen or so Death Eaters on broomsticks had almost closed in and raised their wands when Professor Flitwick gave the order to attack. I whipped my wand through the air and sent a Stunning Spell towards them. Their tight formation broke and they scattered, evading most of our spells. However, some did hit their mark, and three cloaked bodies fell silently from their broomsticks. The surviving figures returned fire, and the tower once again shook under a fierce barrage of curses.

I cried out in pain as a falling piece of masonry slashed my shoulder. Out of the corner of my eye, I saw a thick window pane strike Mandy Brocklehurst on the head. She crumpled to the ground at once.

'No –!' I choked in the cloud of dust, scrambling through the rubble to her side.

I had barely reached her when Cho knelt down beside me, ghostlike in appearance from the layer of white dust that covered her body. Together, we lifted Mandy from the ground and staggered into the common room through the broken window. Glass crunched under our feet as we walked over the dusty carpet, and we set her down carefully next to Michael Corner, who was lying unconscious beside the fallen statue of Rowena Ravenclaw.

We heard Professor Flitwick give a muffled shout from outside, which was drowned out by the gleeful bellows of the Death Eaters flying by. More curse flew through the windows, exploding off the tapestries and glass-fronted bookcases of the common room. I left Mandy with Cho and Roger and stumbled back to the battlements. To my horror, I saw that a section of the parapet had fallen away, leaving a gaping hole in our defences. I looked desperately around at our group of fighters and realised that our number had shrunk. Stephen was on his hands and knees, coughing in the rubble. I flung myself down at his side.

'Hey, are you alright?'

'Yeah … yeah – I'll live,' he said gruffly, wiping away a trickle of blood from his mouth.

'Where's Kevin?' I asked quickly.

Stephen's eyes widened and he glanced left and right. Just as my panic was beginning to mount, Kevin staggered through the smoke towards us.

'Alright?' he said, clapping us both on the shoulder.

I gave a weak smile and Stephen sighed in relief.

'We can do this. Let's not lose faith yet,' said Kevin confidently.

I stood up and pulled Stephen to his feet. The three of us stood side by side, staring grimly over the broken parapet. Below us, the battle was getting even more intense. Countless flashes of light streaked back and forth across the grounds, and as we watched, a large section of the Quidditch stands collapsed in flames. To our right, a twittering cloud of owls rose, hooting in terror, from the fiercely burning Owlery. Another distant explosion sent plumes of smoke and fire towards the sky from the roof of the Great Hall, and the castle quaked again.