'It's Potter.' He whirled around. Wand, bag, what else?.. 'It's got to be Potter.'

'Wait,' Dumbledore said patiently.

'They might be captured, and they're heading here anyway.'

'If you go out now, you're more likely to miss them and leave the school weakened.'

'And if I don't go out now, and they are taken, then your dream about Potter's demise finally comes true.' Broom! Where was his bloody broom?

Albus cocked his head to the side, amazed.

'Are you going to protect him? Where? In a barely defensible castle with several hundreds of potential hostages?.. If he didn't have to be taught and make acquaintances among his peers, I'd never have him here in the first place! I took him out of Hogwarts when I thought the Dark Lord was going to attack either of us! And you can't blame Harry for the actions of your enemies,' Dumbledore finished kindly.

'Ah yes, I keep forgetting that bit.'

'Aberforth has just concealed them in his pub. They will be here shortly.'

Snape sighed through his nose and flicked his wand in a pattern of the strongest belief of his heart.

Four does stood before him, and the office became brighter and warmer.

'Go to McGonagall, Flitwick, Sprout and Pomphrey and have them come here – except Flitwick, who is to patrol the corridors for Potter, Granger, Weasley, Carrow… if there is anyone else out, he is to communicate it via a portrait.'

They vanished, and he unlocked his more powerful arsenal. A Time-Turner. A dozen bottles of Luck. A pack of Dung Bombs, deserving capitalization. A stack of unopened Howlers from Mrs. Longbottom. A vial of Basilisk's finest, which he personally collected some five years ago (people thought Slughorn was weird, going to such lengths for the sake of a spider's venom; little did they know.)

Somebody knocked.

'Come in!'

It was Professor McGonagall, prim as ever. She frowned at the mess on the floor and Transfigured an armchair into a low table.

It was then that he knew for certain she was on his side.

'When?'

'Just now.' Silver needles, unpolished but very sharp. 'Do you have aught to add?' A keg of gunpowder. A page from Lily's letter… should he burn it?

'WINKY!'

The Elf appeared instantly, eyes round.

'Take this,' he rolled it up and thrust into a pouch. Too late, too late – Potter was coming, he had to be ready… 'Bury it near the Tomb. And warn the others that you will be accompanying students – they are underage and cannot protect themselves without arousing the Ministry's attention. Then come back.'

'Leave Hogwarts?' Winky asked, and her ears trembled.

'Do what I said!'

'I have healing potions,' said Minerva over the crack of Disapparation.

'Bring and sort them.'

She left through the Floo. There was the sound of more people arriving. Sprout, Sinistra and Firenze (on whose back Poppy was sitting sideways) filed in without asking permission.

'What are you doing here?'

'Awaiting a chance for revenge,' replied the blind one, unruffled.

'You have been invalided out of action!'

Barely were the words out of his mouth when he found himself bent backwards and pinned to a shelf of Dumbledore's ticking things by a hoof the size of a saucer, tucked under his chin.

'I have just cleared him,' said Poppy happily. 'Firenze, my friend, spare the Headmaster.'

The hoof pressed in very gently before letting him slip down.

'You do realize that those who remain here will be tramped into the ground by forces a hundred times stronger?' he asked, very much not whining. 'Pomona, you will chaperone the children, and that's an order.'

She didn't like it, but she saw the necessity and didn't argue. Poppy took some convincing, but in the end he simply overrode her objections.

Sinistra just plainly refused to go.

'Severus, 'I said so' isn't an argument.'

'You are a Master of Astronomy. It's not a battle technique.'

'I am trained in basic Defense and can navigate the upper levels better than any of you.'

'If they reach the upper levels, it means we have lost.'

'No, it doesn't – '

Slughorn opened the door, turned his head this way and that way and squeezed his way in. Two gagged, blindfolded, bound and thoroughly senseless bodies floated behind him into the cramped office.

'Good evening, ladies and gentlemen.'

'Are these – ?' Snape stared at his official Deputies, bobbing companionably up and down an inch below the ceiling.

'I thought I'd better take measures,' explained the venerable Potions Master.

'May I come in?' asked the annoyed voice of Madam Pince. 'Firenze, this might be the most revealing viewpoint – '

The centaur hastily helped Poppy down and trotted further in, squashing those in his way. Snape extinguished the fire in the Floo and enlarged it with a spell, so that he could settle into the improvised niche. He saved his display of weapons in the last moment (and wasn't it a tad invigorating, stretching himself over glass holding the most powerful toxin in Britain.)

He noticed quite a few things on the table which he hadn't put there, too – vials and small charmed balls and daggers and such.

'Well!' said Horatio when everybody quieted down. 'What's the plan?'

'The plan?'

'I assume Mr. Potter is going to join us?' said Pomona, pouring tea.

'Presumably,' he said, perplexed. Wait; there was something wrong about the whole thing. 'Why are you here?'

They sighed and snickered and looked at him with tolerant amusement.

'Somebody tell him we aren't children,' Poppy muttered. 'Albus?'

'I am not sure,' Albus replied, eyes twinkling. He looked to Minerva (she had come back at some point, Snape knew not when). 'I seem to recall a girl with long hair and a fondness for short skirts, forever carrying piles of books. She kept darting around the place Transfiguring things when nobody was watching. Where has she gone to?'

'At this time of night?' Minerva raised a queenly eyebrow. 'Surely she's out Patrolling.'

They smiled at each other, and Snape was stung by a sudden sense of rightness; this was what he should have built in his years of pedagogy. The relationship between Master and Students, who would have studied not for the sake of exams, but for the sake of science. Albus had been very fortunate with Minerva, like Horatio – with Lily and himself (though Horatio could be said to be too fortunate, what with the Dark Lord and all.)

He vowed silently but unbreakably that he would live through this and become a better teacher.

'Since when have you been conspiring?' He couldn't decide between 'to help me' or 'against me'.

'Since you were appointed.'

'We did adjust our goals along the way.'

'We thought you'd catch on,' said Vector, smirking. She was armed with a large ruler. 'Remember that arithmantic problem I presented you with at dinner?'

'All of them.'

'The one about Indian customs? When Filius made such a blunder?'

'What are you talking about?'

'There is a chance that the gipsy would use only seven birds. Or six. Or even one measly crow – though the likelihood of that is really small.'

'And?'

'He said it would be eight to twelve,' explained Sinistra. 'It was a political statement, not a solution.'

'Oh great.' And he used to spy for the Order. 'What else did I miss?'

'Everything?' Minerva asked innocently.

'We talked where you could see us, Severus. We don't have a lot of free time, you know.'

'Yes, there are those dratted homework assignments…'

Just then the door opened again, and in came Filius Flitwick, Harry Potter, Hermione Granger, Ron Weasley and Luna Lovegood.

The students looked stunned, then (Weasley and Potter) tried to draw on them. Snape wasn't even sure who disarmed them (and the other two, just to be safe).

'What on Earth is going on?' Potter demanded.

'As you have seen in the memories I sent you –' began Snape.

'What memories?' asked the boy, too surprised to launch an offensive.

(The Potter Factor, pure and simple.)

'Of our conversations,' Albus said gravely. 'Severus is, and has always been, fighting for us.'

Potter's mouth fell open, and then closed again, betraying his anger.

'But we haven't received any message from you,' said Granger, looking puzzled and wary.

'How? I specifically Confounded him so that he would give it only to you…'

'Confounded whom?'

'The only man close to Albus whom the Death Eaters failed to suspect…'

Everybody frowned at him without comprehension. But really, wasn't this obvious?

'The only man who had both the freedom and the motivation to follow through on this…'

'Snape?'

'For the sake of his brother's memory.'

Silence.

'Ah,' said Dumbledore, fiddling with his glasses again. 'Severus, I'm afraid you really should have consulted me first.'