AN: So, how did you like the prologue? I deliberately didn't give names to the husband and wife couple as I wanted to see who would be able to guess their identities; all will be revealed in the fullness of time… Another short chapter just to set the mood; a little teaser from the last book and then AU and non canon for the rest of the tale.

Professor McGonagall moved faster than Harry could have believed: her wand slashed through the air and for a split second Harry thought that Snape must crumple, unconscious, but the swiftness of his charm shield was such that McGonagall was thrown off balance. She brandished her wand at a torch on the wall and it flew of its bracket: Harry, about to curse Snape, was forced to pull Luna out of the way of the descending flames, which became a ring of fire the filled the corridor and flew like a lasso at Snape –

Then it was no longer fire, but a great, black serpent that McGonagall blasted to smoke, which reformed and solidified in seconds to become a swarm of pursuing daggers: Snape avoided them only by forcing a suit of armour in front of him, and with echoing clangs the daggers sank, one after the other, into its breast-

'Minerva!' cried a squeaky voice, and looking behind him, still shielding Luna from flying spells, Harry saw Professors Flitwick and Sprout sprinting up the corridor towards them in their nightclothes, with the enormous Professor Slughorn being shepherded along the corridor by an out of breath Hermione.

'No!' squealed Flitwick, raising his wand. 'You'll do no more murder at Hogwarts!' Flitwick's spell was aimed at the suit of armour behind which Snape was hiding but instead of hitting the errant Headmaster, the spell was immediately rebounded and the corridor was filled with a dazzling white light that temporarily blinded them all. 'That's got rid of him for a while.' Flitwick bounced on his feet as soon as the corridor cleared and he saw that Snape was no longer hiding behind the armour.

'Don't be a fool Filius, do you really think that pesky charm would be enough to stop a Death Eater?' Minerva pointed her wand at the shattered window at the end of the corridor. 'He simply used it as an opportunity to conceal his escape.'

'You mean he's dead?'

'Unlike our dear Dumbledore, Snape was still carrying his wand when he jumped…and he seems to have learnt a few tricks from his master.' McGonagall said bitterly as the small group watched a huge bat-like shape flying through the darkness towards the perimeter wall. She glanced down at the disappointed look on Flitwick's face. 'What were you hoping would happen, Filius?'

'It should have been powerful enough to blast Snape out of existence, or at least send him somewhere we wouldn't have to worry about him for oh, about twenty years or so…'

'A portable time turner charm? Oh Filius you know those charms haven't been sanctioned for wizarding use since those unfortunate Mayans decided to try them,'

'Well it didn't work anyway, so there's nothing to worry about.' Filius grumbled under his breath as he stashed his wand in his pyjama sleeve.

'Harry,' Luna tugged on Harry's arm and drew him away from the window: her lightly accented tones holding a note of worry. 'Where's Hermione?'

'What do you mean, she's right over…' Harry started to point over to where Hermione had been standing directly next to Slughorn and everyone turned around as his words trailed off. 'I mean, she was right there.'

'Filius! You reverse the spell this instant!' Minerva screeched, her soft Scottish burr completely disappearing as she rounded on the poor charms professor who was quivering in his slippers as he faced the wrath of the very angry witch.

'I can't Minerva, once the spell is cast there is no reversal…'

'Professor, no…there has to be some way.' Harry cried out, his youthful face seeming to age five years in the last few seconds, and Slughorn pressed his hand to Harry's shoulder.

'Harry, my boy…I'm sure if there were a way to bring Miss Granger back Filius and I will find it.' Harry suddenly gasped, his hands flying to his forehead. He could see images flying through his mind and smelt the tang of seawater in his nostrils.

'He's coming, we've got to barricade the school.'

McGonagall snapped to attention and straightened her gown, forcing herself to speak. 'As much as it pains me to say this, especially to you Potter: but we have to put Miss Granger's disappearance to the side for now. From what I can recall of the Tempus charm, the subject is merely moved through time and not location; for now Miss Granger is somewhere in the school, but just not in this time. I suggest we establish basic protection around the place, then gather our students and meet in the Great Hall. Most must be evacuated, though if any of those who are over-age wish to stay and fight, I think they ought to be given the chance.' McGonagall looked at her fellow teachers and once they gave their nods of agreement, she turned her attention back to Harry. 'Potter, I believe you and Miss Lovegood should start your search somewhere near the Ravenclaw common room; we'll try and give you as much time as we can. Good luck to you both.' Harry reluctantly agreed, knowing that there was nothing they could do about trying to find Hermione with the threat of Voldemort looming over their heads. He grabbed Luna's hand and together they hurried off toward the Ravenclaw tower located on the west side of the castle. McGonagall watched them run off before pulling out her wand and directing it at the large stone statues and suits of armour lining the hallways.

'Piertotum Locomotor! Hogwarts is threatened!' McGonagall shouted, flicking her wand to the main staircase. 'Man the boundaries, do your duty – protect our school!' Crumbling pieces of stone and dust fell to the floor as the statues creaked to life, each one lining up before marching off to form a protective guard around the courtyard and main gate. 'Pomona, Horace – you'd better see to your Houses, get the little ones away; find Longbottom and arrange for them to take them through the Hogsmeade tunnel; Filius and I will take care of the others. I have no doubt that Voldemort will be making a personal appearance very shortly now that Snape has revealed his true nature.' McGonagall cast her gaze out of the shattered window once more, before urging her fellow professors to head down to the Great Hall to start closing down Hogwarts for what may be the final time.

AN: Any recognisable parts are rightfully credited to JK Rowling; Harry Potter and The Deathly Hallows