Fan Casting

One year after Otto Octavius's sacrifice to save New York City, Peter Parker plans to propose to Mary Jane Watson, who has just made her Broadway musical debut. Later a meteorite lands at Central Park, and an extraterrestrial symbiote follows Peter to his apartment. Harry Osborn, seeking vengeance after his father's death, attacks Peter with weapons based on his father's Green Goblin technology. The battle ends with Harry crashing out and developing amnesia, wiping out his memory of Peter as Spider-Man. Meanwhile, police pursue escaped convict Flint Marko, who visits his wife and dying daughter before fleeing again, and falling into an experimental particle accelerator that fuses his DNA with the surrounding sand, transforming him into the Sandman, with powers to control sand and to deform at will. During a public festival honoring Spider-Man for saving Gwen Stacy's life, he kisses her, infuriating Mary Jane. The super-powered Marko robs an armored car, and Spider-Man confronts him. Marko easily subdues Spider-Man, and escapes. NYPD Captain George Stacy informs Peter and Aunt May that Marko was Uncle Ben's true killer; the deceased Dennis Carradine was Marko's accomplice. As Peter sleeps in his Spider-Man suit waiting for Marko, the symbiote assimilates his suit. Peter later awakens on top of a building, discovering his costume changed and his powers enhanced; however, the symbiote also brings out Peter's dark side. Wearing the new suit, Spider-Man locates Marko and battles him in a subway tunnel. Discovering that water is Marko's weakness, Spider-Man breaks a water pipe, causing water to reduce Marko to mud and wash him away. Peter's changed personality alienates Mary Jane, whose career is floundering, and she finds solace with Harry, but leaves afterwards in regret. Harry recovers from his amnesia and, urged by a hallucination of his father, blackmails Mary Jane into breaking up with Peter. After Mary Jane tells Peter she loves "somebody else", Harry meets with Peter and claims to be "the other guy". Peter confronts Harry about forcing Mary Jane to end her relationship with him and spitefully tells Harry that his father never loved him. Another fight ensues, in which Harry throws a pumpkin bomb at Peter, who deflects it back, disfiguring Harry's face. Peter then exposes rival photographer Eddie Brock, who created photos depicting black-suit Spider-Man as a criminal to get the staff photographer job. Peter proves his plagiarism, which results in their boss, J. Jonah Jameson, firing Brock, printing out a retraction and giving Brock's job to Peter. Later, to make Mary Jane jealous, Peter brings Gwen to a nightclub, where Mary Jane now works. Realizing this, Gwen leaves the nightclub, and, after being told to leave, Peter attacks a couple of bouncers and he accidentally hits Mary Jane. Peter now realizes how the symbiote is corrupting him. Retreating to a bell tower of a church, Peter removes the symbiote after bumping into a church bell weakens it, which falls below to the floor and bonds with Brock, who in turn, praying for Peter's death, is transformed into Venom. Brock locates Marko and convinces him to join forces to defeat Spider-Man. Posing as a taxi driver, Brock kidnaps Mary Jane, and holds her as bait from a web high above a construction site, while Marko keeps the police at bay. Seeking help, Peter goes to Harry, who rejects him. While Spider-Man battles Brock and Marko, Harry learns the truth about his father's death from his butler, and goes to the construction site to help Peter, resulting in a battle between the four. Harry subdues the Sandman before assisting Peter against Brock. In the ensuing battle, Brock attempts to impale Peter with Harry's glider, but Harry steps in, and is impaled himself. Remembering the symbiote's weakness, Peter assembles a perimeter of metal pipes to create a sonic attack, weakening it, and allowing Peter to separate Brock from the symbiote. Peter activates a pumpkin bomb from Harry's glider and throws it at the symbiote, but Brock, attempting to become Venom again, dives in and is killed along with the symbiote. After the battle, Marko explains that Uncle Ben's death was an accident, and that his uncle was trying to help him. His death has haunted him ever since. Peter forgives Marko, who then leaves. Peter and Mary Jane accompany Harry, who dies peacefully from his injuries. Peter, Mary Jane, and Aunt May attend Harry's funeral. Later, at the nightclub, Peter and Mary Jane reconcile and dance.