Dumbledore reached the ramparts first, quickly dismounting with Harry close behind him. They looked around. The tower was completely deserted and there was no sign of any disturbance but still the Dark Mark, with its ever watchful eyes, hovered above.
"They're here, Professor. Death Eaters. Do you think someone's really…dead?" Dumbledore did not answer his question. He was leaning heavily against the stone wall and breathing loudly.
"Find Severus. Bring him to me as quickly as possible and keep your cloak on." Harry hesitated, loathe to leave him alone in his weakened state. "Go Harry." The urgent tone of his voice jerked Harry alive. He rushed to the door towards the spiral staircase but as he reached it, footsteps sounded on the other side. Harry jerked back, pressing his body against the cold tower wall, as the door swung open.
"Expelliarmus," a voice commanded and instantly Harry was frozen in his spot. He couldn't even move his jaw to speak. Expelliarmus isn't a freezing charm, he thought confusedly. But he registered the sound of a wand clattering to the floor and saw Dumbledore standing alone and empty handed. He had wordlessly frozen Harry under the invisibility cloak and simultaneously sacrificed his last chance for self defense. The intruder bowed to pick up Dumbledore's wand and drew closer to the light to face the professor. A flash of golden hair told Harry everything he needed to know.
Draco circled the headmaster, an expression of gloating on his face that was discernible as false only to Harry. Dumbledore however, didn't look perturbed in the least.
"Good evening, Draco," he said calmly.
"Where's Harry?" said Draco, his voice steely. "I know he was with you."
"He is gone," said Dumbledore, waving a hand towards the seemingly empty tower. "As you can see."
"Where? Where did you send him?"
"Away. He is out of your reach tonight." Draco's face relaxed into a perfectly blank expression but his hand began to shake on the wand. "You needn't be afraid, Draco. I'm sure you've done exactly what they asked of you." Draco's face lost its passiveness and contorted into one of rage. Harry thought he looked almost insane.
"I'm not afraid," he screamed. "It's YOU who should be afraid!"
"Why? I don't think you are going to kill me. Oh, you may hold me here until your friends arrive and so actively contribute to my demise, but you won't point the wand yourself. Murder is much easier to promise than it is to carry out." Draco, still shaking, said nothing. "So while we're waiting for your companions to arrive, why don't you tell me how you did it?"
"I did it," said Draco, panting. "I did it right under everyone's nose. You never suspected." He was staring not at Dumbledore, but at some far off point just to the left of his head. Into empty space.
"Did you now?"
"I used the Room of Requirement," Draco said. He didn't seem to even hear the headmaster's words. "And a pair of vanishing cabinets from…from Borgin and Burkes." He was breathing heavily now.
"Very clever." Dumbledore's face remained placid.
"I placed Madame Rosemerta under the Imperious Curse. I had her slip Katie Bell the necklace in the girl's room at the Three Broomsticks." His words were no longer a taunt, they were a confession. "I've been trying to kill you. All year." Under the invisibility cloak, his words were like fire in Harry's ears. He tried to block them out, to pretend they were just sounds and he didn't understand their meaning, but he couldn't. Draco went on.
"Snape betrayed you." Harry's stomach dropped to his feet but Dumbledore said nothing. "He wants you dead. He's one of the Death Eaters here tonight." Draco was no longer angry or shaking. Instead, he was a robot. A rigid, expressionless machine, made only to stand in one place and tell the truth whether it was asked of him or not. Harry couldn't bare it.
"You won't kill me, Draco," Dumbledore said gently.
"Yes, I will."
"No, you won't."
"Yes, I will." But there was no fight in Draco's voice.
"Draco, it's not too late. You've harmed no one. Put your wand down now. I can help you."
"No one can help me." His voice was completely hollow. "I don't have a choice."
"There is always a choice, my boy." There was no discernible change in Draco's face, but his body sagged in defeat. His shoulders relaxed and his arm began to slowly lower his wand when-
The door to the Astronomy Tower burst open and four Death Eaters in mussed robed filed in. Harry's heart sank as he thought about what that meant for the outcome of the battle below. Bellatrix LeStrange waltzed over to Dumbledore, accompanied by two men whom Harry didn't recognize and one who must have been Fenrir Greyback. He was extraordinarily hairy and dirty, with long whiskers protruding from his cheeks. He smelled of sweat and blood that probably wasn't his own.
"Dumbledore disarmed and cornered! Well done, well done Draco!" one of the men said shrilly. Draco was frozen in place, as frozen as Harry was. They continued to marvel over the fine job for a few more moments, to relish in Dumbledore's capture, when a sound of scuffling from below reminded them of their present situation.
"Go ahead, Draco," Bellatrix purred. "Finish him." Draco didn't move. The other Death Eaters tensed and looked at each other.
"You have your orders, boy," said the other man coldly. "You must carry them out. Kill him now!" Still Draco didn't move. His eyes were wide but they didn't seem afraid, only empty and far away. Fenrir Greyback, who up until that point had been apart from the conversation eyeing Dumbledore, raised his head.
"You'll hurry up and kill him if you know what's good for you," he sneered.
"No," Draco slowly lowered his wand. Greyback's eyes narrowed. He approached Draco slowly until he was almost chest to chest with him, towering over the boy by at least 8 inches.
"What did-"
"I said no," said Draco, letting Dumbledore's wand fall from his other hand with a clatter.
The tower was eerily silent. Suddenly, footsteps sounded on the stairs and a moment later, Snape flung open the door.
"Severus, we have a problem," the second man said. "The boy seems incapable or…unwilling to perform his task." Snape smirked and pushed past Draco.
"Suddenly grown a conscience, have you? Then get out of my way." He raised his wand-
A bolt of red light shot from Draco's wand and hit Snape in the back. He fell to the ground, stupefied. Bellatrix screamed and leapt for Draco, shooting white light at him, which he blocked.
"Cru-" But before she could finish the unforgivable curse, Draco turned and disapparated with a crack. Slowly, Snape struggled to his feet.
"Find him," he hissed. "He's somewhere in the castle. Find him!" The three remaining Death Eaters flew from the tower and tore down the steps. Snape turned to Dumbledore. Harry screamed wordlessly.
"Severus, please."
"Avada Kedavra."
