At Azkaban, in Sirius's cell:
"I shouldn't be here. It's all Peter's fault, not mine! Poor Lily and James, if it wasn't for bloody Peter, they would still be alive! I knew he was trouble. And I warned them." cried Sirius!
Flashback:
"Lily, James, It's me Sirius. Peter is going to betray you tonight. You must leave with Harry ASAP. This is for your own good." I dropped the telephone. I knew they wouldn't get the message in time. Even if they did, they wouldn't believe me. I have to go stop Peter, before it gets too late!
Lily and James's House:
"Bloody hell, there he is!"
"Go away Sirius this isn't the time."
"No Peter, it is. You betrayed Lily and James , your best friends, to Voldemort! How could you, Peter?"
"I, I, I don't know what you are talking about."
"Oh, I think you do. And I'm going to turn you in, you betrayer!"
"I don't think so Sirius"
Peter swiftly whipped out his want and cast a spell on his index finger. It fell to the ground.
"What are you doing Peter?"
The last thing Sirius saw of Peter was a small smirk as Peter quickly turned himself into his animagus form, a rat, and scurried into the sewer. Sirius was left standing in awe, at the scene of the crime, when the Dementors arrived.
Back at Azkaban:
"I will get revenge on that Peter, if it isn't the last thing I do!He hasn't seen the last of me!"