Wizards were dueling everywhere Remus turned, their shouted incantations and flashes of spell-light flooding the darkened amphitheater with color and noise. Remus had never been inside the Department of Mysteries before, but he knew this room by reputation: it was called the Death Chamber, centered around a stone dais holding an ancient archway and a fluttering black veil that served as a physical, visible barrier between the worlds of the living and dead. It was certainly not the location Remus would have chosen for a confrontation between Voldemort's followers and the Order, but it was where they had found Harry, and so it was here they were making their stand.

Rabastan Lestrange sent a jet of flames flying for him, but Remus dove out of its way just in time and incapacitated his attacker with a swift Body-Bind Curse. With Rabastan taken care of, he clambered down the rows of stone benches towards where Harry stood with Neville Longbottom, the two of them facing off against Antonin Dolohov. Neville's legs were flailing wildly—a result of the Tarantallegra jinx, no doubt—and Dolohov was going to curse Harry next…. Remus raised his wand to intervene, but Sirius was closer; he threw himself at the Death Eater and drew him away from the students, goading him into a duel.

Remus whipped around at the sound of a crash behind him, followed by the delighted cackling of Bellatrix Lestrange: she had Stunned Tonks, her own niece, and now Tonks was tumbling limply down from bench to bench, unconscious and entirely vulnerable to attack. Heart pounding, Remus was about to run to her when he heard the snarling voice of Lucius Malfoy behind him, crouched over Harry with his wand pressed to his chest. "Give me the prophecy, Potter," he was saying.

Harry threw the glowing glass sphere that held his prophecy to Neville and flung Lucius back against the dais with an Impediment Jinx. His eyes alight with fury, Lucius climbed back to his feet to attack again, but Remus leapt in front of him and protected Harry and Neville with a swift Shield Charm. "Harry, round up the others and go!" he called.

Lucius was still focused on the students, using a Reductor Curse to blast away the bench on which Harry was struggling to pull up Neville—out of the corner of his eye Remus saw the prophecy slip from Neville's pocket and shatter, revealing its secrets to a room in which it could not be heard; Lucius had seen it, too, and Remus used this distraction to Stun him with a well-placed jinx to the face. It didn't matter that the prophecy had been destroyed, at least not for the Order: Dumbledore already knew its words by heart.

Now that Lucius was out of the way, Remus glanced around to assess the others, finding to his relief that no Death Eater had yet taken advantage of Tonks's helpless state to finish her off; Bellatrix was engrossed in a duel with Sirius now, grinning as she sent curse after curse flying for her cousin. But Sirius's reflexes were as sharp as they had always been; he would be fine, he always was.

And then his eyes fell on Dumbledore, leaping down the benches with his wand raised and his face taut with fury. Remus's heart leapt; the Death Eaters had no chance now that he'd arrived. Several of them screamed, cutting off their duels mid-spell—Crabbe attempted to flee the chamber at the sight of the old headmaster, but Dumbledore yanked him back with a simple flick of his wand.

Sirius and Bellatrix were the only ones still fighting, standing about ten feet apart from each other in the center of the dais. Sirius was backpedaling towards the archway and the veil; Remus hastily yelled out a warning to him, but Sirius didn't seem to hear.

"Come on, you can do better than that!" he sneered at Bellatrix as he ducked away from her Stunning Spell. He was so close to the veil now, way too close….

His taunt had only just left his lips when another of his cousin's Stunning Spells hit him full-on in the chest. Remus saw his eyes widen as his body was flung backwards, back into the archway….

Time seemed to slow while Sirius fell, his head disappearing behind the veil first and the rest of him following until there was nothing of him left to make impact with the ground. The veil rippled as it absorbed him, mind and body and soul, every essence and fragment of Sirius Black; and then it calmed again, going nearly still as if nothing had disturbed it at all.

Remus felt for a moment as though he were detached from himself, floating above the world or sinking deep beneath it—then Harry flashed by him, running towards the archway, and instantly he returned to his senses. Harry was going to follow Sirius through the veil, it was going to take him too….

Remus rushed after him and wrapped his arms around Harry's chest, yanking him away from the dais. He was speaking, telling Harry there was nothing he could do; his words were emerging all on their own, derived from some strange outside force, but they caught in his throat when he tried to say because he's dead and wouldn't come anymore. Harry kicked and screamed and fought, but somehow Remus found enough strength to resist him.

In a heavy, hazy trance, he dragged Harry back over to where Neville was lying and removed the Tarantallegra jinx from his legs. Remus turned away from the veil and asked where the others were, Harry's other friends who had followed him to the Ministry…then there was a shout and a bang from the other side of the room, and Bellatrix, who'd been dueling Kingsley, cried out and took off for the door out of the chamber.

Remus's grip on Harry had gone slack; he broke free easily now, running after Bellatrix. "She killed him—I'll kill her!" Remus called after him, his gaze fixed on his retreating figure, but he did no more to stop him. She killed him…she killed him…she killed him.

"Professor Lubin," Neville said from the crumbling bench below, speaking around a bloodied, broken nose. "Professor Lubin…."

But Remus didn't answer, because his eyes had found the veil again and he no longer felt anything like Professor Lupin—he was once again the scared, lonely werewolf boy he'd been when he first arrived at Hogwarts, the boy who had kissed Sirius fiercely from the sidecar of his motorbike and lay with him after full moons in the hospital wing and held his hand in the dark corridors of the castle. Sirius was so much of who he was—his first love, his last best friend—that Remus wasn't sure how much of himself could exist without him. His mother, James, Lily…he'd lost so much, nearly everyone he loved, he couldn't take any more of it…and now Sirius had fallen through the veil into death, and he was never going to see him or hold him again…he hadn't even left a body behind to bury….

The trance that had briefly deadened Remus's emotions had melted away now—he felt suddenly that he could no longer support his own weight. He collapsed against the stone bench beneath him, ignoring Neville's startled expression, and let out an ear-piercing, wordless scream, the sound of his grief and anger reverberating around the chamber until every last shred of his breath was gone.