Gary Oldman: Sirius Black
Sirius Black : I expect you're tired of hearing this, but you look so like your father. Except your eyes. You have...
Harry : My mother's eyes.
Sirius Black : It's cruel that I got to spend so much time with James and Lily, and you so little. But know this; the ones that love us never really leave us. And you can always find them in here.
[puts his hand to Harry's heart]
Professor Snape : Expelliarmus! Ah, vengeance is sweet. How I hoped I'd be the one to catch you.
Professor Snape : I told Dumbledore you were helping an old friend enter the castle and now here's the proof.
Sirius Black : Brilliant, Snape - once again you've put your keen and penetrating mind to the task and as usual come to the wrong conclusion. Now if you'll excuse us, Remus and I have some unfinished business to attend to.
Professor Snape : [raises his wand at Black] Give me a reason. I beg you.
Professor Lupin : Severus, don't be a fool...
Sirius Black : He can't help it. It's habit by now.
Professor Lupin : Sirius, be quiet!
Sirius Black : Be quiet yourself, Remus!
Professor Snape : Listen to you two, quarrelling like an old married couple.
Sirius Black : Why don't you run along and play with your chemistry set?
Professor Snape : [puts his wand to Black's throat] I could do it, you know... But why deny the Dementors? They're so longing to see you.
Professor Snape : Do I detect a flicker of fear? Ah, yes. The Dementor's Kiss. One can only imagine what that must be like to endure. It's said to be nearly unbearable to witness, but I'll do my best.
Sirius Black : Enough talk, Remus! C'mon, let's kill him!
Professor Lupin : Wait!
Sirius Black : I did my waiting! Twelve years of it! In Azkaban!
Professor Lupin : Very well, kill him. But wait one more minute. Harry has the right to know why.
Harry : I know why! You betrayed my parents! You're the reason they're dead!
Professor Lupin : No, Harry, it wasn't him! Somebody did betray your parents, but it was somebody who, until quite recently, I believed to be dead.
Harry : Who was it then?
Sirius Black : Peter Pettigrew! And he's in this room, right now! Come out, come out, Peter! Come out and play!
Sirius Black : Sorry about the bite, I reckon that twinges a bit.
Ron : A bit? A bit? You almost tore my leg off!
Sirius Black : I *was* going for the rat. Normally, I have a very sweet disposition as a dog. In fact, more than once, James suggested that I make the change permanent. The tail I could live with. But the fleas? They're murder.
Sirius Black : It's beautiful, isn't it? I'll never forget the first time I walked through those doors. It'll be nice to do it again as a free man.
Sirius Black : That was a noble thing you did back there. He doesn't deserve it.
Harry : Well, I just didn't think my dad would've wanted his two best friends to become killers. Besides, dead the truth dies with him. Alive, you're free.
Sirius Black : You know the man you truly are, Remus! This heart is where you truly live! This heart! Here! This flesh is only flesh!
Harry : Tell me about Peter Pettigrew!
Professor Lupin : He was at school witth us, we thought he was our friend.
Harry : No, Pettigrew's dead.
Harry : You killed him.
Professor Lupin : No he didn't! I thought so too, until you mentioned seeing Pettigrew on the map.
Harry : The map was lying, then.
Sirius Black : The map never lies! Pettigrew's alive.
Professor Lupin : [as Snape points his wand at Sirius's throat] Severus, don't be a fool...
Sirius Black : He can't help it, it's habit by now.
Professor Lupin : Sirius, be quiet.
Sirius Black : Be quiet yourself, Remus!
Professor Snape : Listen to you two, quarreling like an old married couple...
Sirius Black : [in a mocking voice] Why don't yo run along and play with your chemistry set?
[Snape pushes wand harder on Sirius's throat]
Professor Snape : I could do it, you know. But why deny the Dementors? They're so longing to see you... do I detect a flicker of fear? Ah, yes, the Dementor's Kiss. One can only imagine what that must be like to endure. It's said to be nearly unbearable to witness, but I'll do my best.
[Harry unnoticeably pulls Hermione's wand out of her pocket]
Sirius Black : Severus, please!
Professor Snape : After you.
[gestures Sirius toward door]
Harry : [to Snape] Expelliarmus!
[Snape flies backwards onto a bed, unconscious]
Ron : Harry! What did you just do?
Hermione : You attacked a teacher!
Harry : [to Lupin] Tell me about Peter Pettigrew!
Professor Lupin : He was at school with us! We thought he was our friend!
Harry : No, Pettigrew's dead!
[whirls around at Sirius]
Harry : You killed him!
Professor Lupin : [jumps in front of Sirius] No he didn't! I thought so, too until you mentioned seeing Pettigrew on the map!
Harry : The map was lying, then!
Sirius Black : That map never lies! Pettigrew's alive! And he's right there!
[points at Ron]
Ron : Me? He's mental!
Sirius Black : Not you! Your rat!
Ron : Scabbers has been in my family for...
Sirius Black : Twelve years! Curiously a long life for a rat! He's missing a toe, isn't he?
Ron : So what?
Harry : [about Ron's rat missing a toe and being Peter Pettigrew] All they could find left of Pettigrew was his...
Sirius Black : Finger! But then the coward cut it off so they would think he was dead! And then he transformed into a rat!
Harry : Show me.
[Sirius tries to take the rat from Ron, but Ron holds onto it]
Harry : Give it to him, Ron.
Ron : What are you trying to do to him?
[Sirius finally gets a hold of the rat]
Ron : Scabbers! Leave him alone!
[tries to run toward Sirius, but Hermione holds him back]
Ron : Get off him! What are you doing?
[Sirius drops the rat, which runs while Sirius finally transforms it into Peter Petitgrew]
Peter Pettigrew : [realizes he's not a rat anymore] Remus, S-Sirius? My old friends!
[runs toward the door, but Lupin and Sirius block him]
Peter Pettigrew : Harry, l-look at you!
[walks toward Harry]
Peter Pettigrew : You look so much like your father! Like James, we were best friends!
Sirius Black : How dare you speak to Harry!
[Pettigrew scowls and runs away from Sirius]
Sirius Black : How dare you talk about James in front of him!
Professor Lupin : You sold James and Lily to Voldemort, didn't you?
Peter Pettigrew : I didn't mean to! The Dark Lord. You have no idea the weapons he possesses! Ask yourself, Sirius! What would you have done? What would you have done?
Sirius Black : I would have died!
[Pettigrew crawls under piano]
Sirius Black : I would have died rather than betray my friends!
Peter Pettigrew : [runs over to Harry, whispering to him] Harry, James wouldn't have wanted me killed! Your dad... your dad would have spared me! He would shown me mercy...!
[Lupin and Sirius yank him off Harry]
Sirius Black : You should have realized, Peter, that if Voldemort wouldn't kill you we would!
[he and Lupin pull out their wands and point them and Pettigrew]
Sirius Black : Together!
Harry : No!
Professor Lupin : Harry, this man is...
Harry : I know what he is, but we'll take him to the castle.
Peter Pettigrew : Bless you boy, bless you!
[kneels to Harry]
Harry : Get off me! I said we'll take you to the castle. After that, the dementors can have you.
Sirius Black : Only one will die tonight.