The film opens with a frenzied emergency response as FDNY, the NYPD, and ambulances converge on a collapsing building. A woman recently through a painful breakup stands at a breaking point, but Spider-Man [Nicholas Hammond] rescues her at the last moment, and the onlookers erupt in applause for the masked hero.
At New York State University, Dr. Baylor [Simon Scott] unveils a plan to run a plutonium experiment, a prospect that unsettles Peter and his fellow students who fear the danger such a test could unleash. Into this tense atmosphere steps Gale Hoffman [JoAnna Cameron], a determined journalist eager to secure an interview with Spider-Man after the rescue, sensing that the wall-crawler’s actions could become the stuff of a bigger story.
Chaos erupts when three students exploit the lab’s materials and steal plutonium to demonstrate the dangers of nuclear power by building an improvised bomb. Spider-Man [Nicholas Hammond] shows up to intervene, but the theft is soon noticed by security, and the scene spirals out of control. When one of the activists collapses from radiation exposure, the others abort their plan and rush the injured colleague to the hospital. The fallout is swift and severe: law enforcement pins the blame on Spider-Man, and Inspector DeCarlo [Sidney Clute] directly confronts Peter Parker, creating a web of confusion and suspicion around the teen chemist.
Meanwhile, far away in Switzerland, Mr. White [Robert Alda] reads a newspaper clipping about the theft and deduces the culprits were the students, not the hero. He hatches a more personal plan: steal the plutonium for his own ends. He heads to the United States with his fearsome henchman Angel [Lawrence P. Casey], intent on seizing the weapon for a more menacing purpose.
The chase intensifies as White targets Peter, attempting to kidnap him to uncover the plutonium’s whereabouts. Peter escapes, and the pursuit erupts into a clash with White’s followers. Spider-Man battles the henchmen and is hurled from a tall building, seemingly meeting a fatal end; he saves himself by weaving a web to catch the fall. In the ensuing confusion, White escapes with the bomb, forcing Spider-Man to confront a foe who plans to unleash chaos on major cities.
With the stakes rising, J. Jonah Jameson [Robert F. Simon], the abrasive owner of The Daily Bugle, learns that White has slipped away to Los Angeles. He sends Peter Parker and Gale Hoffman on a cross-country pursuit to track the mastermind down, hoping to avert catastrophe before he can trigger a catastrophe of his own design. The race shifts to the West Coast as the clock ticks toward a presidential speech that White intends to use as cover for a massive strike.
White’s audacious scheme targets Los Angeles, a city about to be graced by a presidential address. The authorities assume the motive is to cripple New York, but White’s true plan is to detonate the plutonium bomb during the high-profile moment in Los Angeles, testing his weapon’s reach and striking fear into millions.
In a tense, high-stakes finale, Spider-Man locates White’s lair, discovers the doomed device, and defuses the bomb at the last possible second. The narrow escape of catastrophe leaves White unceremoniously free, and he vows that the two will cross paths again. The city recovers in the aftermath, while the vigilant hero understands that the fight against nuclear danger—and the people who manipulate it—will continue.
