SCORPIUS: "I need your help."

SNAPE: "Dumbledore? Dumbledore's dead. And my work for him was public -- I taught in his school."

SCORPIUS runs into the Potions classroom, slamming back the door. SEVERUS SNAPE looks up at him.

SCORPIUS: "But you're the answer…"

SNAPE: "Professor Snape will do fine. You may behave like a king at this school, Malfoy, but that doesn't make us all your subjects."

SNAPE: "Did no one teach you to knock, boy?"

SNAPE: "How very pleasant for me. If you've got something to say, boy, then please say it… If not, close the door on your way out."

SCORPIUS: "I just don't know what help I -- need. Are you still undercover now? Are you still working secretly for Dumbledore?"

SCORPIUS: "Severus Snape. This is an honor."

SCORPIUS looks up at SNAPE, slightly breathless, slightly unsure, slightly exultant.

SNAPE: "I exist to serve."

SCORPIUS: "No. That's not all you did. You watched the Death Eaters for him. You advised him. Everyone thought you'd murdered him -- but it turned out you'd been supporting him. You saved the world."

SNAPE: "I'd say that the rumors of Hogwarts's beloved Scorpion King losing his mind are well-founded."

SNAPE: "These are very dangerous allegations, boy. And don't think the Malfoy name will prevent me inflicting punishment."

SNAPE: "Harry Potter won that Triwizard Tournament."

SCORPIUS: "He wasn't supposed to do it alone. Cedric was supposed to win it with him. But we humiliated him out of the tournament. And as a result of that humiliation he became a Death Eater. I can't work out what he did in the Battle of Hogwarts -- whether he killed someone or -- but he did something and it changed everything."

SCORPIUS: "What if I was to tell you there was another world -- another world in which Voldemort was defeated at the Battle of Hogwarts, in which Harry Potter and Dumbledore's Army won, how would you feel then…"

SCORPIUS: "There was a stolen Time-Turner. I stole a Time-Turner. With Albus. We tried to bring Cedric Diggory back from the dead, when he was dead. We tried to stop him winning the Triwizard Tournament. But by doing so we turned him into an almost different person entirely."

SCORPIUS: "You loved his mother. I don't remember everything. I know you loved his mother. Harry's mother. Lily. I know you spent years undercover. I know without you the war could never have been won. How would I know this if I hadn't seen the other world…?"

SCORPIUS: "Oh, of course, that's it! Professor Longbottom was supposed to kill Nagini, Voldemort's snake. Nagini had to die before Voldemort could die. That's it! You've solved it! We destroyed Cedric, he killed Neville, Voldemort won the battle. Can you see? Can you see it?"

SNAPE looks at SCORPIUS -- unsure what's going on. Is this a trick? He is quite seriously at a loss.

SCORPIUS thinks and then plays his final, desperate card.

SNAPE says nothing, overwhelmed.

SNAPE: "I can see this is a Malfoy game. Get out before I alert your father and plunge you into deep trouble."

SNAPE: "Cedric Diggory killed only one wizard and not a significant one -- Neville Longbottom."

SCORPIUS: "Only Dumbledore knew, am I right? And when you lost him you must have felt so alone. I know you're a good man. Harry Potter told his son you're a great man."

SCORPIUS: "Not in my world. He said you were the bravest man he'd ever met. He knew, you see -- he knew your secret -- what you did for Dumbledore. And he admired you for it -- greatly. And that's why he named his son -- my best friend -- after you both. Albus Severus Potter."

SNAPE is stopped. He is deeply moved.

SNAPE: "Colloportus!"

An invisible lock slams into place. SNAPE opens a hatch at the back of the classroom.

SCORPIUS: "Okay, who's we?"

SNAPE: "Harry Potter is dead."

SNAPE thinks and then walks up to SCORPIUS, taking out his wand as he does. SCORPIUS steps back, scared. SNAPE fires his wand at the door.

SNAPE: "We've had to move many times. Everywhere we've settled they destroyed. This will take us to a room hidden in the roots of the Whomping Willow."

SCORPIUS: "Just a question, but where -- exactly -- are we going?"

SCORPIUS: "Please -- for Lily, for the world, help me."

SNAPE: "Well, come on, then…"

SNAPE: "Oh. You'll see."