The film kicks off with Teddy Jackson (Kevin Hart), who is attempting to film a promotional video for his fitness business. Clad in a sweatsuit and wielding elastic bands, his efforts at non-contact boxing fall comically flat. Meanwhile, in an isolated desert, an enigmatic assassin known as The Man From Toronto (Woody Harrelson) arrives at a cabin, ready to extract information from a suspect. Just as Toronto is about to exert a brutal interrogation with a heated knife, the suspect succumbs to fear and spills the needed details. However, as soon as Toronto departs, the suspect is coldly executed by an associate.
As Teddy prepares to celebrate his anniversary with his beloved wife Lori (Jasmine Mathews), she admires him but cannot ignore his chronic misfortunes—so much so that her colleagues have coined the term "Teddying things up" for mistakes. Teddy has arranged a romantic getaway at an AirBNB, but due to a "low toner situation," he misreads the address. At his workplace, he faces the ire of his boss, Marty (Martin Roach), for fumbling the gym flyers lacking vital contact information. Although Marty appreciates Teddy, he reluctantly fires him.
Returning home, Toronto is contacted by his Handler (Ellen Barkin), who explains that he must take on a lucrative contract—$2 million. Meanwhile, Teddy arrives at the spa for their anniversary celebration. After dropping off Lori, he accidentally wanders to the wrong cabin, the very one that Toronto's target is supposed to be at. Convinced Teddy is the hitman, the thugs capture him and take him to the basement. In a moment of panic, Teddy tries to reassure their hostage, ultimately leading to the hostage revealing what the criminals want.
Suddenly, the basement is invaded by FBI agents, apprehending everyone, including the utterly confused Teddy. During interrogation, it becomes apparent to the agents that Teddy is certainly not their target, but they require "The Man From Toronto" to infiltrate a former Venezuelan Colonel named Sebastian Marin (Alejandro De Hoyos), who once orchestrated a coup. To maintain their cover, the agents implore Teddy to impersonate Toronto, which leads to further complications. As they assign Agent Santoro (Jencarlos Caneda) to look after Lori, Teddy feels insecure about Santoro’s charm and handsomeness. He fabricates a story about attending a work conference, hiding the fact that he has just been fired.
Toronto, upon hearing of this mix-up, discovers Teddy's workout videos and tracks him down just as he meets with Daniela (Lela Loren). Instead of a straightforward encounter, things take a turn when Toronto steps in, and a sequence of chaotic events leads them to a brief altercation mid-flight to Puerto Rico, where they become allies in the midst of turmoil involving Marin’s henchmen.
As they crash-land in a field, Toronto resolves to hunt down a certain Mr. Green who has crucial information. The two find themselves at a tech convention where Teddy has to engage in some intense and nerve-wracking interrogation, mistakenly slashing a man's face and even causing a commotion that nearly leads to his unmasking. In the backdrop, another hitman, The Man From Miami (Pierson Fode), lurks, awaiting his chance to eliminate Toronto.
Upon maneuvering through various misadventures, including an unexpected dinner with Lori and her friend Annie (Kaley Cuoco-Sweeting), wherein lies a confrontation with Miami that spirals out of control, Teddy’s dual life becomes increasingly precarious. With the FBI on their trail and deceit swirling around them, Teddy and Toronto's partnership develops as they begrudgingly trust each other while evading The Handler’s deadly plans.
In a climactic showdown involving miscommunication, confrontations with numerous other assassins, and a harrowing escape, Teddy ultimately stands up to Miami. The narrative intertwines their fates, leading to a final confrontation where loyalties are tested. Teddy's heartwarming reunion with Lori after surviving chaos allows him to redeem himself, even as he inadvertently leaves Toronto’s prized car in a disastrous situation.
Fast forward a year later, and Teddy and Lori are expecting their first child. Toronto’s dreams of culinary success take shape as he opens his restaurant, while Teddy’s fitness venture flourishes. Yet, lingering tensions remain, as Toronto embarks on a quest for revenge against Teddy for the automotive disaster, setting the stage for future hilarity. The film wraps up with a blend of comedy, action, and heartwarming moments, encapsulating the ups and downs of Teddy’s chaotic life.
