Officer Frank Dooley (John Candy), a dedicated member of the LAPD for a decade, finds his career abruptly derailed when he is wrongfully accused of stealing a television. This injustice is perpetuated by two corrupt detectives, who he had previously exposed while they were robbing an appliance store. Though he escapes criminal repercussions during his court appearance, he faces the humiliation of being dismissed from the police force.
In the following court case, inept and timid defense attorney Norman Kane (Eugene Levy) is seen grappling with the daunting task of defending a dangerously aggressive cult leader, Lawrence Lupik (Glenn Withrow), whose threats loom heavy over him. It becomes clear that Kane must succeed, as Lupik menacingly asserts that a failure to win his case will result in dire consequences for Kane himself. The judge, Stacy Keach, Sr., seizes on Kane's palpable fear, giving a grim warning that Lupik would receive “a sentence so long he won’t even remember his own name, let alone yours,” insisting that Kane should consider a career shift that comes with “a lot less responsibility.”
The fates of Dooley and Kane intertwine when they both seek employment at a budget-conscious security firm, Guard Dog Security, managed by the gruff Captain Clarence O'Connell (Kenneth McMillan). Here, they learn that their new line of work involves maintaining absurdly high membership dues to the security guards' union, represented by Clyde Klepper (Jonathan Banks) and Tony Lazarus (Brion James). After a brief training session, Dooley and Kane are licensed as armed security guards and paired by Maggie Cavanaugh (Meg Ryan) for their night shift at the Carlex Pharmaceutical warehouse.
Their first night on duty descends into chaos when they are instructed by the senior guard Bruno (Tom Lister, Jr.) to take a lunch break, leading to a brazen armed robbery. Kane inadvertently stumbles into the robbery and desperately calls Dooley for aid, yet the robbers, masked and armed, overwhelm them with machine guns. Fleeing into an “Annex” area that Bruno warned them to avoid, Kane finds himself pursued by trained dogs until Dooley arrives just in time, employing unorthodox methods—such as biting and punching—as he battles the aggressive canines.
The following day sees the duo facing severe reprimands from O'Connell, who issues each a $100 fine for their failure to prevent the robbery. Both Kane and Dooley grow suspicious about the fairness of their punishment, especially when they learn O'Connell is Maggie’s father—a revelation that adds further tension to their working relationship. The duo's discontent rises during a union meeting where they confront Michael Carlino (Robert Loggia), the union president, questioning the opaque management of their hefty dues. Carlino, irritated by Kane's inquiry regarding the union's multi-million-dollar finances, threatens him physically before dismissing the meeting abruptly.
As they proceed with their assignments, which increasingly feel like punitive measures for Kane’s earlier comments at the union meeting, they end up working in undesirable locations like a landfill and a toxic waste site. Here, they hear troubling tales from seasoned guards about another robbery linked to their previous assignments, fueling their determination to uncover the truth behind these incidents of corruption.
The bumbling partners, spurred by a mix of naivety and desperation, track down Bruno at a gym, using the threat of heavy weights to extract a confession. Bruno reveals O'Connell's ulterior motives, confirming suspicions that the captain knowingly put them in harm's way that fateful night. Soon after, they visit Cappy (Tony Burton), an old thief friend of Dooley's, who informs them about Carlino’s malicious dealings with the union's funds and his connection to organized crime.
Determined to gather concrete evidence, Dooley and Kane don tuxedos and infiltrate a fancy dinner hosted by Carlino. Their antics lead them to overhear a conversation about a nefarious plan to rob an armored truck, utilizing the union's pension money in dubious dealings that could threaten their livelihoods. Unbeknownst to them, this eavesdrop leads to a critical turning point when they realize they must stop Carlino’s plot and save an innocent life.
When the stakes rise, and they find themselves framed for murder, a thrilling chase ensues across Los Angeles as they evade both corrupt and well-meaning authorities. Hiding in a bookstore and disguising themselves as an outrageous couple, the comedic misadventures provide both laughs and tension as they concoct a plan to thwart the robbery.
With intention and bravery, Dooley, Kane, and Maggie devise a scheme to preemptively strike against the criminals. Dooley’s travels on a motorcycle ultimately lead him to a timely rendezvous with a reckless trucker, Cowboy (Steve Railsback), adding yet another wild layer of chaos to their already tumultuous night. As the final confrontation unfolds, Dooley musters courage and resourcefulness, engaging in a dramatic fight against Carlino’s henchmen and ultimately assisting law enforcement in rounding up the culprits.
In the thrilling denouement, justice prevails, and Police Chief Bruce Kirby invites Dooley back into the fold as a decorated detective, where Kane begrudgingly contemplates rejoining the fray, yearning for the safety of his previous profession. The culmination of their odyssey serves as a testament to their resilience and determination to uncover the truth amidst an ocean of corruption and peril.
