Big Dave, editor of the Daily Print tabloid, is snubbed by cannabis baron Mickey Pearson at a party and hires private investigator Fletcher, to investigate Pearson’s links to Lord Pressfield, a Royal Duke with a heroin-addicted daughter. Fletcher offers to sell his findings (typed up as a screenplay entitled Bush) to Pearson’s right-hand man, Raymond, for £20,000,000.
Pearson plans to sell his business to American billionaire Matthew Berger for $400,000,000 so he can retire peacefully with his wife, Rosalind. Pearson shows Berger one of the labs where he grows his cannabis under the estates of aristocratic landlords, who need cash for the upkeep of their stately homes. Pearson is later approached by Dry Eye, an underboss for Chinese gangster Lord George. Dry Eye offers to buy out Pearson’s business, but he refuses. Pearson’s lab is then raided by amateur MMA fighters and aspiring YouTubers “The Toddlers” who overpower the lab’s guards, steal a van-load of marijuana and upload a rap video of their caper online. The fighters’ trainer, known only as Coach, orders them to delete the video and is horrified when he discovers that the cannabis belongs to Pearson.
Pearson begins transferring his cannabis plants out of the estates. He also agrees to bring home Pressfield’s wayward daughter Laura. Raymond retrieves Laura from a council estate where she is living with several other addicts. However, in a brawl with her flatmates one of Raymond’s men accidentally pushes Aslan, a young Russian man, out of the window to his death. Although Laura was then returned to her parents, she later dies of a heroin overdose. Coach visits Raymond, apologises for his students’ actions, and offers his services as penance. Coach has captured Phuc, a henchman of Dry Eye’s who had informed Coach’s crew about the lab location, although Phuc is accidentally killed during a botched escape attempt. Pearson threatens Lord George for going after his lab, and destroys one of his heroin labs in retaliation. George chastises Dry Eye for his insubordination in attacking Pearson and offering to buy him out; George nods to a henchman to execute Dry Eye, but the man executes George instead.
Unknown to Pearson, Dry Eye is in league with Berger, who had wanted Pearson’s business disrupted to reduce the price. Dry Eye has taken Lord George’s place and still hopes to take Pearson’s empire for himself. Dry Eye tries to kidnap Rosalind, who kills Dry Eye’s men before she runs out of bullets in her two-shot derringer. Raymond kills an assassin sent to kill Pearson; the two rush to Rosalind and Pearson kills Dry Eye. Fletcher ends his story and Raymond orders him to leave his house.
Fletcher has merely confirmed Pearson’s suspicions about the link between Dry Eye and Berger. Raymond orders Coach’s students to capture Big Dave. They drug him and film him having sex with a pig, threatening to post it online unless he drops his investigation. Pearson and Berger meet up again in a frozen fish plant, actually a cover for Pearson’s European distribution operation. Berger drops his offer to $130,000,000, on account of the recent disruptions it has experienced, but Pearson reveals his knowledge of Berger’s plan, shows him Dry Eye’s frozen body and tells him he is keeping his business. Pearson forces Berger inside a refrigerator, where he will freeze to death unless he transfers $270,000,000 compensation and, for the assault on Rosalind, cuts “a pound of flesh” from his own body.
Fletcher approaches Raymond again for his payment, but Raymond reveals that he was tailing Fletcher all along. The fighters have stolen his stashes of evidence after Raymond placed a tracker on him during their last encounter. Fletcher reveals that he has also sold info to Aslan’s father, a Russian oligarch and former KGB agent. Coach kills two Russian hitmen sent to kill Raymond, while Fletcher escapes in the chaos. Pearson is kidnapped by two other Russians, but they are ambushed by Coach’s students who want to “solve Coach’s problem”. They assault the car with bullets, killing the Russians and allowing Pearson to escape. Later, Fletcher decides to pitch the story as a film to Miramax. After his meeting, he gets into a cab only to realise that Raymond is the driver. Upon learning of Fletcher’s capture, Pearson and Rosalind return to their cannabis empire and celebrate in each other’s company.