The story takes place in suburban New Jersey. TS Quint arrives at his girlfriend Brandi Svenning's, house to pick her up for a road trip to Florida. She meets him in the driveway and tells him she won't be able to go; she's been asked by her father to fill in for a woman who was supposed to appear on her father's TV show (an poor imitation of The Dating Game). Quint's offhand remark to the original contestant the night before resulted in her obsessively swimming laps at the local YWCA pool until she died from a brain embolism.
Quint believes that Brandi is simply bending to the will of her overbearing father, who dislikes Quint to begin with. Quint had also been planning to propose to Brandi at Universal Studios in the Jaws spectacular. The couple have a serious argument that ends with Quint leaving.
Meanwhile, in the basement of his own home, Quint's best friend, Brodie, is woken by his girlfriend, Rene. Brodie is largely indifferent to her presence & the two have a heated conversation where she finally dumps him for many reasons, mostly his lazy & shiftless attitude & his ignorance about how much she cares about him. Brodie has never introduced Rene to his mother and she resents having to climb in his basement window to spend the night with him. She throws him a break-up letter and climbs out the window over his protests.
Quint goes to Brodie's house after leaving Brandi & the two try to figure out what to do with the rest of the day. Brodie tells Quint about his being dumped and the two discuss their relative situations. They finally decide to go to the local mall & hang out.
They arrive at the mall & find out that a stage setup is being constructed. It turns out that Brandi's father is going to be staging his dating show in the mall for the public to see the taping and because a couple of television executives will be present & he hopes he can further his own career. Brodie suggests that he & Quint find a way to sabotage the show out of revenge. They find the mall's resident troublemakers, Jay and Silent Bob, in front of the pet store and enlist their help to wreck the stage setup and the show. However, the two already know they must find a way to either distract or take down the mall's top security guard, a hulking man named La Fours.
Jay and Silent Bob's plans are all blundered attempts that end in failure. They are constantly pursued by La Fours and the other mall cops and manage to escape much of the time. Though they draw up intricate blueprinted plans for their missions, they are thwarted every time.
Meanwhile, Brodie and Quint try to reconcile with their respective former girlfriends. Brodie notices that Rene is being schmoozed by the general manager of a mall men's store, Shannon, whose ultimate plan is simply to get Rene into bed. Brodie manages to get Rene alone in the elevator and following a heated argument, they have sex. Rene is still not impressed enough to take Brodie back. When Shannon hears about the tryst, he takes Brodie into a back corridor of the mall and beats him up, saying that Rene's not interested and that he's only using her for sex.
Quint is also unsuccessful at reconciling with Brandi, who shows up at the mall to dress for the dating show. Quint has a few conversations with Mr Svenning to try and convince him that he's a decent enough person to be dating Brodie, but Svenning is totally unconvinced. When Brodie joins the conversation, he plays a nasty trick on Svenning: he "stinkpalms" him, shaking his hand and handing him chocolate-covered pretzels after he'd inserted a few of his fingers in his own rectum. Svenning, however, had simply been stalling the duo and has them both arrested (they are rescued moments later by Jay and Silent Bob, who knock out their mall cop captors).
Brodie suggests that to avoid further pursuit, that they go to a nearby flea market. While there, they seek the advice of a psychic, Ivannah, whose gimmick is to read people's fortunes topless. (She also has 2 nipples on her right breast, adding to her panache.) She gives Quint some advice; that he shouldn't give up trying to reconcile with Brandi, despite what her father thinks. The two return to the mall and reconnect with Jay and Silent Bob to enact a more elaborate plan of revenge.
One of the mall's denizens is a 15-year-old student named Tricia. Tricia is conducting a study of the male sex drive and her research involves having sex with men aged 18 - 60. She has also videotaped them all with their consent. One of the people she'd slept with is Shannon. Brodie asks to borrow the tape she'd done with Shannon.
Behind the scenes of the dating show, Jay has been sent to subdue two of the male contestants with marijuana. Brodie and Quint take their places on the show. A third contestant was missed by Jay. They also knock out Svenning's personal assistant. Svenning himself is sidelined by a case of diphtheria, which he'd caught from Brodie's stinkpalm prank, and spends most of the show vomiting.
On the program, Quint, Brodie & the third contestant, Gill Hicks, will compete for a date with Brandi. Brandi asks them several pointed questions about their dating style and soon figures out that Quint and Brodie are behind the wall that hides them from her. Quint is able to win Brandi back with clever answers and the two reconcile on stage. Brodie takes the microphone from the host & points out Rene in the audience, telling her that Shannon is a lecherous bastard. While he's seized by the security guards, Silent Bob, who'd wired a VCR unit into the stage's monitor, plays Tricia's tape of Shannon having sex with her. Brodie announces that Tricia is an underaged girl and Shannon is arrested. Svenning is also arrested for the video being shown on local television, and for the scatological remarks the Brodie made as a contestant. Rene admits she loves Brodie and gets back together with him. He invites her to dinner at his house so she can meet his mother.
The TV execs tell Svenning that they're not impressed with his show, calling it derivative and dull. They offer Brodie the chance to host his own talk show, which he enthusiastically accepts. The final montage shows Brodie on his own show; Brandi and Quint get married at the Jaws spectacular in Florida; Tricia's book is a bestseller for over a year; Svenning and his assistant are shown doing television in prison; Jay and Silent Bob set out West with an orangutan (a lead-in for their adventures in Jay and Silent Bob Strike Back).