The success of the film led to three sequels, all co-written by the same three writers and directed by DeBello.
The film opens with a scroll saying that when Alfred Hitchcock's film The Birds (1963) was released, audiences laughed at the notion of birds revolting against humanity, but when an attack perpetrated by birds occurred in 1975, no one laughed. This is followed by a pre-credits sequence of a tomato rising out of a woman's garbage disposal unit. Her puzzlement turns into terror as the tomato draws her into a corner. Following the credits, the police investigate her death. One officer discovers that the red substance she is covered with is not blood, but tomato juice.
A series of attacks perpetrated by tomatoes occur (including a man dying by drinking tomato juice made from a killer tomato, a boy heard being gobbled up by a killer tomato, and a sequence where the tomatoes attack innocent swimmers, in a parody of Jaws). While the President's press secretary Jim Richardson tries to convince the public that there is no credible threat, the president puts together a team of specialists to stop the tomatoes, led by a man named Mason Dixon. Dixon's team includes Sam Smith, a disguise expert who is seen at various points dressed as, among other things, George Washington, Abraham Lincoln and Adolf Hitler; scuba diver Greg Colburn; Olympic swimmer Gretta Attenbaum; and parachute-toting soldier Wilbur Finletter.
Smith is sent out to infiltrate the tomatoes at a campfire, eventually blowing his cover while eating a hamburger and asking if anyone could "pass the ketchup." Colburn and Gretta are sent to sectors, while Finletter stays with Mason. Meanwhile, the president sends Richardson to the fictitious ad agency "Mind Makers," where executive Ted Swan spends huge amounts of money to develop virtually worthless ploys including a bumper sticker with "STP" for "Stop Tomato Program" on it, a satirical reference to both the real "whip inflation now" campaign with its widely ridiculed "WIN" slogan and STP motor oil decals and bumper stickers which were commonplace in the 1970s. It is revealed that a human is also plotting to stop Dixon when a masked assassin attempts to shoot him, but misses. A senate subcommittee meeting is held where one secret pamphlet is leaked to a newspaper editor who sends Lois Fairchild on the story. While she tails Finletter, he mistakes her for a spy and trashes a hotel room attempting to kill her. He then chases the assassin as the masked man fails again to kill Dixon, but loses him.
Gretta is killed and further regression has led leaders to bring in tanks and soldiers to the west coast in a battle that leaves the American forces in shambles. Dixon, walking among the rubble, sees a trail of tomato juice and decides to investigate. He ends up being chased by a killer tomato to an apartment where an oblivious child is listening to the radio. The tomato is about to kill Dixon but suddenly flies out the window. Dixon peers out to see if it has died when he spots the assassin hijacking his car. He chases the assassin in a "slow car chase" that has since been copied by other comedies. Dixon is eventually knocked out by his own car. Awakening, Dixon finds himself captured by Richardson. Though he did not create the killer tomatoes, he has discovered how to control them and plans to do so once civilization has collapsed - leaving him in control. He is about to reveal his secret of control to Dixon when Finletter charges in and runs him through with his sword. Dixon, picking up some strewn records, realizes that he has seen the tomatoes retreat at the sound of the song "Puberty Love" but had not put two and two together until now. He orders Finletter to gather all remaining people and bring them to the stadium. Finletter remarks that "only crazy people" are left in the nearly deserted city, resulting in a motley assortment of people in costumes facing the attacking tomatoes at the stadium.
The tomatoes are cornered in a stadium. "Puberty Love" is played over the loudspeaker, causing the tomatoes to shrink and allowing the various people at the stadium to squash them by stomping on them repeatedly. Fairchild, meanwhile, is cornered by a giant tomato wearing earmuffs, and hence, cannot hear the music. Dixon saves her by showing the tomato the sheet music to "Puberty Love." He professes his love to her, in song. The film ends with a carrot that rises from the soil and says "All right, you guys. They're gone now."
The film also contains the first screen appearance of Dana Ashbrook, then aged 10 or 11, as "Boy on Boat (uncredited)".
The finished film contains footage of a real helicopter crash. In a scene showing law enforcement officers firing their weapons to ward off tomatoes in a field, a $600,000 Hiller Aircraft UH-12E that had been rented for the production was supposed to have landed in the tomato patch behind the officers, but during the landing, its tail rotor struck the ground, causing the craft to spin out of control near the ground, roll over, and burst into flames. The helicopter pilot escaped without serious injury. The crash was caught on film as the cameras were rolling at the time. The crash was later worked into the film. It was done saying of character Von Schauer who survived the crash saying the helicopter was attacked by a "kamikaze" tomato.
The theme song, written by DeBello, describes the tomatoes' rampages through the world, describing that they've killed a man named Herman Farbage while he was taking out the garbage, that the Mayor is on vacation to get out of stopping them, that they've scared off the National Guard and that they've even eaten the narrator's sister. This theme song is used in different variations over the course of the series, here simply sounding like the score of an old monster movie with lyrics and a more catchy tune. All other music was written Gordon Goodwin and Paul Sundfor with lyrics by Dillon, DeBello, and Peace.
The song "Puberty Love" was sung by the then-teenage Matt Cameron, who later became the drummer for Soundgarden and since 1998 has been the drummer for Pearl Jam.
The film has become a cult film.
Variety wrote that the film "isn't even worthy of sarcasm."
There have been a number of sequels and other spin-off material in various media as a result of this movie. They include three movie sequels:Return of the Killer Tomatoes! (1988)
Killer Tomatoes Strike Back! (1990)
Killer Tomatoes Eat France! (1991)
The 1988 sequel, Return of the Killer Tomatoes, the story picks up ten years later. The film is notable for the casting of George Clooney in one of his first film roles.
American composer and orchestrator Gordon Goodwin, one of the original composers for the film, later wrote an Emmy-nominated, big band piece inspired by the music for this film, to be played with his jazz ensemble Gordon Goodwin's Big Phat Band.The film was adapted in 1990 as Attack of the Killer Tomatoes, a cartoon TV series which ran on Fox Kids, but despite the name, it was based on Return of the Killer Tomatoes.
A novel released in 1997, Attack of the Killer Potatoes, pays tribute to the film.
Three different video games were developed: a 1986 video game released for 8-bit computers, which was based on the film, and a 1991 video game released for the Nintendo Entertainment System and Game Boy game consoles, which was based on the animated series.
Viper Comics has released a comic book adaptation of the film in October 2008.
Kim Harrison's book series The Hollows is based in a world where genetically engineered tomatoes killed off a significant portion of the population. The author admitted inspiration came from this movie.
A Greek film has also been made as an homage, I epithesi tou gigantiaiou mousaka (The Attack of the Giant Moussaka) (1999).
In 2008, a remake was announced. Kent Nichols and Douglas Sarine, creators of Ask a Ninja were developing the project. This was to be Nichols' directorial debut. M. Dal Walton III was co-producing along with Emmett/Furla Films. In 2011, John DeBello said that the Ask a Ninja creators were no longer involved. As August 2014, no further updates have been given regarding development of the project.