Peter Pettigrew, also known as Wormtail, was one James Potter's friends and later a Death Eater in the Harry Potter franchise. He appeared in both the books and movies of Harry Potter and the Prisoner of Azkaban, Harry Potter and the Goblet of Fire, Harry Potter and the Half Blood Prince and Harry Potter and the Deathly Hallows.
He was one of James Potter's friends. Later, he joined the Death Eaters and betrayed James and Lily Potter in the process. Peter attended Hogwarts School of Witcraft and Wizardry being sorted into Gryffindor and quickly became friends with Sirius Black, James Potter and Remus Lupin. Peter would join in on James and Sirius's. tormenting of Severus Snape. When Lupin Was discovered to be a werewolf Peter James and Sirius did not abandon him as many others would have instead becoming animagi to support him. Peter also helped Create the Marauders' Map which was used to navigate Hogwarts. Following graduation, all four Marauders joined the Order of the Phoenix to fight Lord Voldemort's death eaters However Peter became a spy for Voldemort and managed to elude suspicion. Peter gave up the location of James and his wife Lily to Voldemort getting them both Killed though Voldemort's physical form was also destroyed.
When a furious Sirius confronted Peter, causing Peter to cleverly yell that Sirius had betrayed the Potters and killed 12 muggles by blowing up the street with a Blasting Curse before then faking his own death by cutting off one of his fingers then turning into a rat and fleeing. Sirius was later arrested for the betrayal and muggle killings. While in rat form, Peter came into the possession of Percy Weasley, who named him Scabbers and later gave him to his younger brother Ron, who was a close Friend of James's son Harry.
Scabbers once bit Gregory Goyle on the knuckle when Goyle tried to steal from Ron and Harry. Ron generally considered Scabbers useless but was devastated When he thought his friend Hemione Granger's car Crookshanks had eaten him nonetheless, though in reality, Peter was scared after hearing Sirius had escaped Azkaban and went to hide in Rubeus Hagrid's hut. Ron later found Scabbers, who tried unsuccessfully to escape being caught by Ron in the shadow of the Whomping Willlow. There, Ron and Peter were dragged into the Shrieking Shack by Sirius.
After a heated discussion and the arrival of Lupin, Peter pleaded for mercy from Lupin and Sirius, who wished to kill him. Harry then talked them into sparing Peter, believing it was what James would want, as well as knowing that Peter had to be alive to exonerate Sirius, creating a life debt between Harry and Peter. When Lupin turned into a werewolf, Sirius had to defend Harry from him. Peter took advantage of the situation and escaped.
Left with no other recourse, Peter decided to travel to Albania and revive Voldemort to get his protection. While on his way to his Master, Peter ran into Ministry official Bertha Jorkins and turned her over to Voldemort. Under torture, Bertha revealed information about the Tri-Wizard tournament that helped Voldemort's plans and location of Voldemort's faithful servant, Barry Crouch Jr. When Voldemort killed her, Peter considered it a mistake, believing they should have modified her memory.
Peter milked venom from Voldemort's snake Nagini to strengthen him and provide him with a rudimentary body. Peter tried unsuccessfully to convince Voldemort to use someone other than Harry to rebuild his body. Peter took Voldemort to the Crouch family home to free Crouch Jr and substigate Crouch Sr. Peter and Crouch Jr then imprisoned Alastor Moody, allowing Crouch Jr to disguise himself as Moody and pose as a teacher at Hogwarts.
Peter was ordered to keep watch of Crouch Sr but neglected his duty, almost sabotaging the plan as Crouch Sr almost escaped. However, Crouch Jr intercepted his father and Peter was punished with the Cruciatus Curse.
Peter played an important Part in Voldemort's resurrection, murdering Cedric Diggory on his orders and performed the ritual on Harry by slicing his arm With a large knife to restore Voldemort to his physical body, even (reluctantly) sacrificing his own hand. Voldemort then rewarded Peter by giving him a silver Hand.
Two years later when Harry, who had been captured by Death Eaters, tackled Peter when he opened the cellar's door to investigate a noise he heard, as did Ron, who managed to take Peter's wand. Peter tried to Kill Harry by strangling him but When Harry reminded Him of his life debt, Peter hesitated, causing an enraged Voldemort to have Peter's silver hand turn on him and strangle him to death. In spite of Harry's hatred for him, he was still horrified that Peter was killed, in a moment of remorse and mercy, things which Voldemort never understood.