- Oscorp (Main story and flashback)
- Mary Jane Watson
- Felicia Hardy
- Green Goblin (Norman Osborn) (Main story and flashback) (First appearance as Green Goblin)
- New York City Fire Department
- New York City Police Department
- Richard Parker (Mentioned)
- Mary Parker (Mentioned)
- Aunt May Parker (Mentioned)
- Hobgoblin (Jason Macendale, Jr.) (Mentioned)
- Dr. Otto Octavius (Mentioned)
Races and Species:
- Earth-92131 (Reality)
- Goblin Formula (First appearance)
- Spider-Man's Suit and Web-Shooters
- Green Goblin Armor (First appearance) (Main story and flashback)
- Pumpkin Bombs
- Hobgoblin Armor (Only in flashback)
- Goblin Glider (Main story and flashback)
Under pressure from the Kingpin, Norman Osborn, and his partner Wardell Stromm attempt to perfect a formula and concoct a gas sample, which the Kingpin requires for use as a chemical weapon. Norman receives a call from the Kingpin telling him that he is running out of time and must manufacture the gas quickly, for his own sake as well as his son Harry's. After, an agitated Norman carelessly begins working on the gas without securing the airline, causing an explosion in the Oscorp building. Spider-Man arrives at the scene, and quickly saves Wardell, who tells him that Norman is still inside. However, Spider-Man is unable to find him, but finds Harry searching through the fire for his father. After being saved by Spider-Man, Harry realises that his father must have perished in the explosion, devastated, as firefighters arrive to put out the fire.
Two weeks later, Harry is invited by the Oscorp board members to a meeting, to negotiate a successor as Oscorp's lead industrialist. This angers Harry, who believes that his father may still be alive since a body was never recovered, blaming the stockholders for mistreating Norman and for his death, before leaving. After the meeting, Kingpin contacts Stromm and orders him to continue working on the gas, despite the recent events.
A goblin begins kidnapping Oscorp board members. When he targets J. Jonah Jameson, Spider-Man interferes and swings onto the goblin's glider, but the Green Goblin crushes his web shooters, before taking off with Jameson. Spider-Man realises that the Green Goblin is similar to the Hobgoblin, whose weaponry originated from Oscorp, and decides to investigate. There, he witnesses Harry searching through some papers, before seeing the goblin leave the building on his glider, and suspects that Harry is the goblin.
After another person is kidnapped, Spider-Man speaks to Detective Terri Lee, who tells him that all who have been kidnapped by the Green Goblin are Oscorp board members. Spider-Man quickly leaves to warn Anastasia Hardy, but the goblin arrives first and kidnaps her and Felicia. Spider-Man saves Felicia, but Anastasia is taken hostage by the goblin, who then intercepts the Kingpin's helicopter and kidnaps him.
Peter visits Mary Jane Watson, who voices her suspicions to him that Harry may be involved in the kidnappings. He secretly agrees with her, but is reluctant to betray his friend and tells her that they must trust Harry, despite the fact that telling her what he really thinks would possibly give him a chance of reconciliation with her. As Mary Jane leaves, Peter sticks a spider tracer to her to protect her from Harry if he is the goblin.
Mary Jane goes to Oscorp, where she finds Harry surveying the wreckage. After she loses sight of Harry, the Green Goblin appears and kidnaps her for spying on him. She is taken to an underwater fortress and held captive along with the Oscorp board members, as the goblin prepares to deal "justice" for the demise of Norman Osborn. He tells them of their sins, before attempting to flood the building. However, Spider-Man arrives and attacks him, before freeing the hostages before they drown. As they escape in a submarine, Spider-Man goes back to fight the goblin. After defeating him, Spider-Man unmasks Norman Osborn, who explains to him that he had survived, gained enhanced strength from the exploding gas, and claimed the Hobgoblin's weaponry at Oscorp. Norman tries to destroy Spider-Man, but his strength wears off and Spider-Man saves him from the flooding complex. Harry appears to help Spider-Man and his unconscious father escape, having discovered how Norman must have escaped from Oscorp through the underground tunnel.
After regaining his health, Norman announces his return to the public. At the announcement, Mary Jane thanks Peter for standing by Harry, and Felicia hands him a note to give to Spider-Man. When Spider-Man arrives at her apartment, Felicia thanks him for saving her mother and for always being there for her, before pushing his mask half-way up his face and - gently, passionately, spontaneously, and gratefully - kissing him, to his surprise.