As the chaos in Bangkok comes to a close, Leslie Chow orchestrates a masterful prison break amidst a riot, effortlessly slipping into freedom. Meanwhile, Alan Garner, grappling with his circumstances, faces an unexpected crisis when he acquires a giraffe, only to horrifically decapitate it while driving under a low overpass. This bizarre incident triggers a tragic chain reaction, culminating in the heart-wrenching collapse of Alan's father, Sid, from a heart attack during a frantic discussion, leaving the family in utter disarray.
After the funeral, Doug Billings, Alan's brother-in-law, confides in Phil Wenneck and Stu Price about a shocking revelation: Alan has stopped taking his ADHD medication, leading to a steep decline in his behavior. Determined to intervene, the trio plans a trip to a rehabilitation facility in Arizona to help Alan regain stability, wagering that they can escort him there without incident.
However, their intentions quickly unravel when a rental truck forcefully rams Phil's minivan off the road, ensnaring the Wolfpack as hostages. They come face-to-face with the sinister crime lord Marshall, accompanied by his menacing enforcer, “Black Doug.” The situation intensifies when Marshall discloses that Chow had stolen half of a $42 million gold stash shortly after their Las Vegas escapades and has been tracking Alan's communications from prison.
In a high-stakes gamble, Marshall takes Doug hostage, threatening the Wolfpack to track down Chow within three days or face dire consequences. In a desperate bid, Alan arranges a secret meeting with Chow in Tijuana, enlisting Phil and Stu to masquerade as tourists in an attempt to ensnare him. Unfortunately, Alan's miscalculation reveals their true intentions, allowing Chow to flip the situation onto them.
Chow cunningly unveils his scheme to reclaim the stolen gold hidden in the basement of a former villa of his. The reluctant group agrees to assist, only to find themselves double-crossed when Chow locks them in the basement, reinstates the security system, and makes off with Phil's minivan. After being arrested and mysteriously released, they are whisked into a sleek limousine that takes them back to the villa, now in Marshall's possession.
Upon arrival, the Wolfpack is astounded to learn that Chow had been manipulating them all along: the gold they had previously stolen was merely the portion Chow neglected to acquire from Marshall. As a grim reminder of their blunder, Chow spares the Wolfpack but eliminates "Black Doug," presenting them with an urgent two-day deadline to locate Chow before everything spirals into chaos once more.
Tracking down Chow through the digital breadcrumb left by Phil's wayward phone at a pawn shop reveals it had been traded for a meager $18,000, far beneath its actual worth of $400,000. The pawn shop owner, Cassie, provides pivotal information that Chow has been visiting an escort service, offering her business card as a conduit for their inquiries. With the help of Stu's former love, Jade, they discover Chow hiding in a lavish penthouse at Caesars Palace. Under the cloak of night, Phil and Alan attempt a stealthy infiltration but end up losing Chow, who descends from the balcony and parachutes onto the vibrant Las Vegas Strip.
Eventually, Stu tracks down Chow and successfully confines him to the trunk of Marshall's limousine, seizing a precious gold brick in the process. Upon their meet-up with Marshall, he is prepared to relinquish Doug, as retrieving the original gold piece appears futile, lost during Chow's escapades in Bangkok. Despite his earlier assurances, Marshall disposes of the trunk with the assumption that Chow is no more. Surprisingly, Alan had secretly aided Chow by providing him with an escape route, just as Marshall discovers the trunk is empty. Chow emerges from the moonroof of the limousine, unleashing a revenge spree against Marshall and his bodyguard while showing mercy towards Phil, Stu, and Doug, thanks to Alan's earlier intervention.
In a surprising gesture, Chow gifts Alan a bar of gold, expressing gratitude for his lifesaving actions. However, Alan declines, stepping away from Chow's influence and thus ending their tumultuous friendship. As the group departs, leaving Chow in his remorse, they head to reclaim Phil's forsaken vehicle from the pawn shop. Meanwhile, Alan opts to linger behind, setting plans in motion with Cassie, marking a pivotal turn in their relationship.
Fast forward six months, as the wedding bells ring, Alan chooses to leave the Wolfpack behind, embarking on a fresh chapter in his life. In a thrilling mid-credits scene, the group, alongside Cassie, finds themselves in the trenches of another wild party, struggling to piece together the night’s events. Stu wakes up wearing a pink lady's thong and sporting breast implants, prompting fragmented memories to surface. Alan recalls that the wedding cake came courtesy of none other than Chow himself.
As the astonishing scene concludes, Chow makes a cheeky appearance from the bathroom, stark naked and wielding a katana. In a raucous finale, the infamous Bangkok monkey drops in from above, cascading onto Stu, who scrambles in sheer terror and disbelief.
