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PROLOGUE

Snape had Draco by the collar as they came sprinting down the stairs of the Astronomy Tower, jumping over the rubble.

"Severus! Wait!" Lupin called out.

Snape's head snapped to Lupin's voice through the smoke from the still falling masonry.

"Go, Draco! Straight to the wards. Stop for no-one. It begins tonight," Snape hissed urgently and pushed the boy forward then swirled to face Lupin who was nearly by his side. Draco just made it away as Snape moved into Lupin's line of sight and away from the rest of the fighters.

"Severus! What's happening? Death Eaters in the castle, is it true?" he gasped between bouts of coughing on the dust from the rubble.

"Dumbledore is dead," said Snape, his face impassive, watching Lupin closely. "Murdered."

"Wha ...?" Lupin couldn't even form the word as his eyes became wide and he swallowed audibly, his eyes darting wildly behind Snape. "It can't be. Severus, no!" Lupin made to get past him to the stairs.

"Where do you think you're going?" Snape blocked Lupin's path, holding Lupin's upper arm to restrain him.

"We can't let his murderer get away! It was a Death Eater, wasn't it?" Lupin asked desperately, his eyes shining, teeth gritted.

"Oh yes," said Snape, a tight, satisfied smile pulling up the corners of his mouth. "Indeed it was. I killed him."

"But ... " Lupin's confusion was comical to Snape as he pulled backwards, staring at Snape, unable to comprehend the admission. "But Dumbledore trusted you! He said ... he said you were on our side." Lupin's voice faltered.

Lupin was so trusting. The old man told Lupin to trust Snape, and the beast was so simple-minded, so pathetically grateful to Dumbledore, he did! Simpleton! If he'd lived up to his primal nature rather than pretending to be a wizard, Snape might have had a use for him, but he was weak ... trusting ... pathetic.

Snape took advantage of Lupin's utter confusion and swiped Lupin's wrist, so quickly and sharply that Lupin's wand clattered on the floor and Lupin cried out in surprise. Snape's wand-tip was at Lupin's throat in an instant, his black eyes hard like drill bits and he moved close to Lupin's ear.

"Werewolf," he whispered. "I was never on your side."

He moved back so he could see the look of utter disbelief in Snape's treachery in Lupin's eyes. Then he smirked.

"AVADA KEDAVRA!"

The green light illuminated the werewolf's expression of sad betrayal briefly, then he fell, lifeless, at Snape's feet. It was an oft-anticipated moment that Snape wished he had longer to savour. Still, there was always the Pensieve for that pleasure.

But now to trap Potter. That would be easy; he heard him thudding down the stairs now. Potter was as foolish as he was predictable. He would follow. Snape ran down the corridor.

"It's over. Time to go!" Snape shouted as he turned the corner at the far end of the corridor, and he set off through the castle, blasting open the great oak front doors, Potter's whelp stopping to check on others (the fool) and then yapping at his heels.

The boy was running full pelt, gaining on them, as they ran across the lawn towards the gates. A Stunning spell flew past Snape's head and he pushed Draco on again. Backing away, knowing the boy would follow, he turned and they raised their wands.

'Cruc-'

Of course, Snape parried the curse, but as much as he'd like to toy with Potter's brat, demonstrate just how woefully weak and inferior the boy was, there was no time for that.

With one sharp arc of his wand, Snape Stupefied Potter who fell heavily, and then Levitated his body through the gates. As soon as they were beyond the gates, Snape pulled Potter's unconscious body to himself and Disapparated.

The Dark Lord would have both the prizes Snape had promised him this night: the death of the old man, and Harry Potter, his horcrux, for safe-keeping.

oOo