When you betrayed Zhan Mu and Lily, you made a fake and ran away.
Became a mouse, named Scabber, lived in the Weasley family for more than ten years, and then became the pet of the boy unknown to the Weasley family, and later became the pet of Ron Weasley.
The left side of his body was tattered, and his front foot was missing a finger, which he deliberately cut off when he was escaping from Sirius' pursuit of fashion death. Sirius found that the mouse in the photo of the Weasleys' trip to Egypt was peter pettigrew in Azkaban, so he escaped from prison and rushed to Hogwarts to kill him, but everyone thought that Sirius was going to kill Harry. The Scabbers found in Crooke Mountain of Hermione were not normal mice. So it contacted Sirius. Finally, Sirius and Lupin showed Scabber's true colors and wanted to kill him, but Harry thought that the dementors should handle it. As a result, Lupin turned into a werewolf, so peter pettigrew escaped. Later, he helped Voldemort recover his body, but he still had some humanity. In the seventh film, he released Harry but was strangled by Voldemort's silver hand.
In the sixth film, Peter lives at Snape's house.
In the seventh film, he didn't release Harry, but Harry and his family were imprisoned by death eaters. Harry, they tried to escape, but Peter found them. Peter and Harry are fighting. Harry lost, and Peter choked him. Harry said, "Don't forget, you still owe me my life." Peter hesitated, but the silver hand Voldemort gave him immediately responded and strangled Peter directly.