Wallace Ritchie embarks on a journey from Des Moines, Iowa, to London, United Kingdom, in order to celebrate his birthday with his brother, James. Unbeknownst to Wallace, his brother is caught up in a business dinner that evening, leaving him with limited entertainment options. To keep his brother engaged, James introduces him to the intriguing world of an interactive improv theatre known as "Theatre of Life." This unique experience allows participants to immerse themselves in an exhilarating crime drama, as they act out roles in a supposedly staged mystery. As the night approaches, James eagerly presents Wallace with a pair of Ambassador cigars, vowing to "fire them up" before the clock strikes midnight to properly celebrate Wally's birthday.
However, things take a dramatic turn when Wallace inadvertently answers a phone call meant for a hitman at the same payphone utilized by the Theatre of Life for their act. The caller, Sir Roger Daggenhurst, mistakenly identifies Wallace as the hired assassin, Spencer, which sets off a chain of events none could foresee. Meanwhile, the real Spencer receives the call intended for Wallace and finds himself committing murder—a shocking act that triggers a police investigation into the unfolding chaos.
As the plot thickens, Daggenhurst, alongside his assistant Hawkins, British Defense Minister Gilbert Embleton, and Russian intelligence agent Sergei, plans to detonate an explosive device hidden within a Matryoshka doll during an important dinner involving British and Russian dignitaries. Their motive? To reignite the Cold War and advance their outdated technology. Wallace, unaware of the true stakes, continues to navigate this treacherous territory, eventually crossing paths with Lori, a call girl entangled in Embleton's web of deception.
Lori harbors plans of her own, scheming to blackmail Embleton with evidence of the plot. With a high-stakes game unfolding, Wallace inadvertently frightens Embleton, who arrives to retrieve crucial letters, while simultaneously driving off Spencer, the real hitman. In a desperate attempt to protect their sinister plot, Daggenhurst hires additional hitmen, and Sergei calls upon the now-inactive spy, Boris "The Butcher" Blavasky, to take care of Spencer. Boris, true to his name, succeeds in eliminating the real threat, but Wallace and Lori manage to escape with the letters before the storm clouds of danger close in on them.
Using Spencer's communicator, Wallace innocently mentions lighting up some “big Ambassadors, at 11:59,” alluding to the cigars James gave him. This cryptic comment is misconstrued by both factions, who now believe Wallace has uncovered their espionage scheme and is an American spy. In a desperate bid for damage control, Daggenhurst offers a hefty sum of 3 million British pounds to Wallace and Lori in exchange for the incriminating letters, orchestrating their rendezvous at the very hotel where the dangerous dinner will take place. Unbeknownst to them, it is merely a deceitful tactic designed to eliminate them.
Throughout this harrowing adventure, Wallace's dynamic with his "co-star" Lori intensifies, especially as she expresses a fervent desire to pursue acting once they secure their payout. As events unfold, Wallace reaches out to his brother James, instructing him to meet him at the hotel. This creates a sense of urgency, compounded by a news report that falsely depicts Wallace as a murder suspect, prompting James to abandon his professional commitments.
Caught in the clutches of their pursuers, Wallace and Lori find themselves imprisoned by the very villains seeking their demise. Boris, eager to resort to less-than-savory methods, prepares to torture James, adding another layer of tension to the already convoluted scenario. Wallace, deftly evading the hitmen, unexpectedly finds himself amidst a spirited group of Russian folk dancers performing for the ambassadors. In an unexpected twist of fate, he discovers the Matryoshka doll bomb, inadvertently disarming it just moments before detonation. The ensuing chaos leads to a crescendo of thrilling heroics as Wallace steals the spotlight with his impromptu dance moves.
As the countdown to disaster fizzles out and the bomb fails to detonate, Sergei and Daggenhurst, realizing their plan has collapsed, present the promised £3 million to Wallace and Lori, while also liberating James, who emerges from his ordeal frazzled but unharmed. Boris, surprisingly congratulatory, acknowledges Wallace's remarkable espionage skills, gifting him a souvenir pistol and hinting at a continuation of his butcher shop business.
In the final moments, as Wallace shares a passionate kiss with Lori, Daggenhurst and Sergei try to flee with half the money, only to inadvertently activate the bomb hidden within Wallace's Matryoshka doll. Their plot concludes in a spectacular explosion, marking the end of their treachery as Wallace unwittingly steps into a world of intrigue. In an unexpected climax, Wallace finds himself on a sun-soaked beach, unknowingly incapacitating a spy as he passes a test for an obscure American espionage group. Mistakenly believing they wish to make him a movie star, Wallace eagerly accepts their intriguing offer, embarking on a new, thrilling chapter of his life.
