In the critical days leading up to the historic Apollo 11 Moon landing, CIA agent Tom Kidman finds himself facing an extraordinary and clandestine mission. He is instructed to hire legendary filmmaker Stanley Kubrick to create a fake moonwalk, preparing for the possibility that the astronauts might be unsuccessful in their groundbreaking endeavor. The CIA sees the Moon landing as a vital ideological victory over the Soviet Union, which they consider necessary to bolster American morale during this tense period.
Armed with a hefty sum of cash in a briefcase, Kidman is given orders to eliminate Kubrick following the completion of this assignment to prevent any leaks regarding their scheme. However, a significant twist complicates the mission when Kidman, unbeknownst to the CIA, is grappling with post-traumatic stress disorder stemming from his harrowing experiences in Vietnam. As a result, he tends to react to frustration with extreme violence, setting the stage for chaotic encounters ahead.
Upon arriving in England, Kidman seeks out Kubrick's agent but mistakenly ends up meeting his agent's cousin, Jonny Thorpe, played by Rupert Grint. Jonny is a struggling band promoter who finds himself in debt to a menacing East End gangster known as the Iron Monger. Despite the mix-up, Jonny agrees to help arrange a meeting between Kidman and Kubrick, enlisting the help of his stoner roommate Leon (portrayed by Robert Sheehan), who is convinced to impersonate the famed director.
During their encounter, Jonny accepts the suitcase filled with cash, promising that the movie will indeed be produced. Mistakenly assuming that Kidman is a Hollywood producer, Jonny and Leon indulge in a financial spree before their world comes crashing down when the Iron Monger’s henchmen break into Jonny's home, assault him, and abscond with the briefcase.
Realizing he was duped, Kidman becomes furious when he sees a news segment about Kubrick and confronts Jonny, who sheepishly admits to his deception. Seeing an opportunity to capitalize on this chaotic situation, Jonny claims that a friend of his named Renatus can fulfill the role of the director. Taken to Renatus's commune-like mansion, the unsuspecting filmmaker believes he is merely embarking on an art project and accepts the task.
While this convoluted plan unfolds, a free-spirited hippie named Ella begins to catch Kidman's eye, deepening the personal stakes in this already complex narrative. Determined to retrieve the stolen briefcase, Kidman recruits Jonny to confront the Iron Monger directly. In a shocking display, instead of negotiation, Kidman resorts to violence, resulting in a series of brutal confrontations where he dispatches several henchmen and recovers the briefcase.
As production gears up, chaos ensues when Renatus insists on turning the film into a performance art piece, confusing the already chaotic atmosphere further. In a misguided attempt to showcase his prowess against marijuana, Kidman takes a hit from a bong that ends up being laced with opium. In a bid to aid his recovery, Ella offers him LSD, inadvertently sending him on a disorienting bad trip. Amid this surreal experience, he confides in Ella and Leon that he no longer wishes to resolve his issues with violence. In a moment of clarity, he attempts to contact the CIA to update them on his status.
Alarmed by his erratic behavior, the CIA dispatches several agents to England, who then take the entire commune hostage to force them to shoot the fake Moon landing. In a manic turn of events, Jonny and Leon don astronaut suits for the shoot, but Leon—overwhelmed and nervous about being on camera—gets high and spirals into a trip on set, stumbling across the faux lunar surface.
Meanwhile, the Iron Monger appears, setting off a violent shootout with the CIA, resulting in significant casualties on both sides. In the midst of the gunfire, the fake footage is successfully broadcast to CIA headquarters. Suddenly, a determined Jonny rushes to protect Kidman from the Iron Monger but is tragically shot in the ensuing chaos. After dispatching the villain, Kidman reassures a shocked Jonny that his astronaut suit absorbed the bullet and falsely claims that Jonny's quick action saved his life.
With the CIA now hunting them down, Jonny, Leon, Kidman, and Ella must flee England. A montage captures the essence of American life during the 1960s, culminating with the actual Apollo 11 Moon landing. As the group arrives in a Spanish bar, they find themselves witnessing the Moon landing alongside locals, leaving them in a state of uncertainty as to whether they are watching history unfold or merely the results of their own dubious filming efforts.
