Set a year after the events of Spider-Man 2, the film follows Peter Parker as he prepares for his future with Mary Jane Watson, while facing Uncle Ben's true killer, Flint Marko, who becomes the Sandman after a freak accident, and Harry Osborn, his former best friend, who is now aware of Peter's identity and seeks to avenge his father; his job at the Daily Bugle is threatened by the presence of a rival photographer named Eddie Brock.

A year after Otto Octavius's sacrifice,[c] Peter Parker plans to propose to Mary Jane Watson, who has made her Broadway musical debut.

[d] Using Norman's performance-enhancing gas and Green Goblin technology, he battles Peter to an eventual stalemate, developing partial amnesia following a fall from his glider.

Publisher J. Jonah Jameson, outraged at Eddie's false photo and having to print a retraction, fires Brock and promotes Peter to staff photographer.

Brock abducts Mary Jane and holds her captive from a web at a construction site, intending to kill her in revenge for Peter ruining him, while Marko keeps the police at bay.

Dylan Baker portrays Dr. Curt Connors, a college physics professor under whom Peter Parker studies, while Willem Dafoe portrays Norman Osborn / Green Goblin, Harry's late father, who returns as a hallucination to encourage his son to destroy Spider-Man, and Cliff Robertson appears as Ben Parker, Peter's deceased uncle in his final acting appearance before his retirement and death in 2011.

Composer Christopher Young appears in the film as a pianist at Mary Jane's theater when she is fired, while producer Grant Curtis cameoed as the driver of an armored car that Sandman attacks.

75-year-old newscaster Hal Fishman appears as himself anchoring the saga of Mary Jane's kidnapping by Venom; he died just fourteen weeks after the movie opened.

"The most important thing Peter right now has to learn is that this whole concept of him as the avenger or him as the hero, he wears this red and blue outfit, with each criminal he brings to justice he's trying to pay down this debt of guilt he feels about the death of Uncle Ben.

[26] While Sandman is a petty criminal in the comics, the screenwriters created a background of the character being Uncle Ben's killer to increase Peter's guilt over his death[31] and challenge his simplistic perception of the event.

[9] Camera crews spent 2 weeks from November 5–18, 2005 to film sequences that would involve intense visual effects so Sony Pictures Imageworks could begin work on the shots early in the project.

[9] Shooting was also difficult for cinematographer Bill Pope, as the symbiote Spider-Man, Venom, and the New Goblin were costumed in black during fight scenes taking place at night.

[44] In addition to the innovative visual effects for the film, Stokdyk created a miniature of a skyscraper section at 1:16 scale with New Deal Studios' Ian Hunter and David Sanger.

Stokdyk chose to design the miniature instead of using computer-generated imagery so damage done to the building could be portrayed realistically and timely without guesswork involving computer models.

[45] In addition to Sony Pictures Imageworks, Cafe FX provided visual effects for the crane disaster scene when Spider-Man rescues Gwen Stacy, as well as shots in the climactic battle.

[44] In a fight where Spider-Man punches through Sandman's chest, amputee martial arts expert Baxter Humby took Tobey Maguire's place in filming the scene.

[54] Following the release of the film, fan research compiled deleted scenes and archival footage, showing Adrian Lester in the role of Dr. Wallace, a molecular biologist working on a cure for Marko's daughter, and an alternate death scene for Venom attempting to reattach itself to Parker, who in turn would have destroyed the symbiote by yanking down a sling of steel rods and creating a sonic attack (although this was depicted in the film's novelization).

[70][71] Techno Source created interactive toys, including a "hand-held Battle Tronics device that straps to the inside of a player's wrist and mimics Spidey's web-slinging motions".

[82] It was the ninth film to play in more than 4,000 theaters upon opening, just after Shrek 2, Spider-Man 2, Shark Tale, Madagascar, Mission: Impossible III, Over the Hedge, Superman Returns and Pirates of the Caribbean: Dead Man's Chest.

[90] Sam Raimi, Tobey Maguire, Kirsten Dunst, James Franco, Thomas Haden Church, Topher Grace, Bryce Dallas Howard, Laura Ziskin, Avi Arad, and Grant Curtis are among those who contributed to the audio commentaries.

While the deal only concerns the United States, titles from Sony Pictures begun to also be added to Disney+ in regions outside of the U.S., as early as June 2022, starting with the majority of the Spider-Man films.

Its Japanese opening generated a total of $3.7 million, making it the country's highest Tuesday gross of any film, breaking the former record held by Harry Potter and the Sorcerer's Stone.

[105] Spider-Man 3 set opening-weekend records in 29 markets[105] including Italy, China, South Korea (the latter was first surpassed by Pirates of the Caribbean: At World's End),[131] India, Singapore, Philippines, Hong Kong, Thailand, Malaysia, Taiwan, Indonesia, Mexico, Brazil, Argentina, Colombia, and Peru.

[149] Robert Wilonsky of Dallas Observer described the film as "overstuffed (three villains), overlong (at more than two hours and 20 minutes) and undercooked (plot points include amnesia and alien goo).

[151] Richard Corliss of Time commended the filmmakers for their ability to "dramatize feelings of angst and personal betrayal worthy of an Ingmar Bergman film, and then to dress them up in gaudy comic-book colors".

[157] His opinion is echoed by Houston Chronicle's Amy Biancolli who complained that "the script is busy with so many supporting characters and plot detours that the series' charming idiosyncrasy is sometimes lost in the noise".

[158] Jack Matthews of Daily News thought the film was too devoted to the "quiet conversations" of Peter and Mary Jane, but that fans would not be disappointed by the action.

[159] Finally, Sean Burns of Philadelphia Weekly felt that the director "substituted scope and scale for the warmth and wit that made those two previous pictures so memorable".

[191] James Vanderbilt was hired in October 2007 to pen the screenplay after initial reports in January 2007 that Sony Pictures was in contact with David Koepp, who wrote the first Spider-Man film.

[214][215] Sam Raimi directed the Marvel Studios film Doctor Strange in the Multiverse of Madness (2022) which sparked renewed interest from fans in making his unproduced Spider-Man 4, a reality.