Vincent "Vince" Chase, portrayed by Adrian Grenier, finds himself at a crossroads after a brief marriage that lasted only nine days. Seeking a fresh start in his career, he reaches out to his former agent and now studio head, Ari Gold, who presents him with an opportunity to lead in his first studio production. However, Vince insists on directing the film as well. At the same time, Ari is managing pressures at home with his wife Melissa (played by Perrey Reeves).
As Vince's circle of friends, including Drama, Eric, and Salvatore "Turtle" Assante (played by Jerry Ferrara), continues to support him, they navigate the ups and downs of Hollywood life together. Eight months later, Vince's directorial debut, Hyde, is deep into post-production but is facing significant troubles: it's $15 million over budget and Ari is feeling the heat from the studio during one of their worst financial years ever.
Despite Ari having yet to see the film, he’s concerned about the mounting expenses as Vince pleads for an extra $10 million. This marks the third time Vince has requested more funding, which frustrates Ari, who is already stressed about the film's financial implications. Defending his decision, Vince argues that he forwent an acting fee to ensure the film's quality, emphasizing that the additional funds would be essential to achieve perfection. He also invites Emily Ratajkowski to the upcoming private screening, hoping to bolster morale.
In an effort to secure the necessary financing, Ari heads to Texas to meet with co-financiers, Larsen McCredle (Billy Bob Thornton) and his son Travis (Haley Joel Osment), who have invested over a billion dollars in the studio without seeing any returns. Hesitant, Larsen sends Travis to attend the private screening in Los Angeles.
Meanwhile, Eric "E" Murphy (played by Kevin Connolly) is poised to welcome a baby with Sloan McQuewick (Emmanuelle Chriqui), but he's entangled in a complicated romance with the seductive Melanie (Sabina Gadecki). Tensions rise as Melanie ends their fling after growing uncomfortable with E’s dual life. Turtle's pursuit of MMA star Ronda Rousey leads to an unexpected invitation to the private screening.
Ari's commitments intensify as his assistant Lloyd is set to get married, and he contemplates officiating the ceremony. However, as the screening date approaches, Vince begins to second-guess the rough cut of his film and opts to cancel the event, fearing it won't resonate with audiences. The party quickly turns chaotic with Drama getting E intoxicated and ending up with another woman named Paula, while Turtle's attempts to charm Ronda hit a snag after a misguided conversation.
As Vince later gives Ari and Travis a copy of the film for review, Ari is impressed, but Travis presents an ultimatum for funding: he demands Johnny "Drama" Chase (played by Kevin Dillon) is cut from the movie, leading to greater conflict. Complicating matters, E faces drama of his own when confronted by both Melanie and Paula about his recent escapades.
When Ari confronts Travis regarding his demands, the tension escalates and leads to Ari being ousted from the production, with Dana Gordon (Constance Zimmer) taking over. Turtle's tenacity pays off when he impresses Ronda and earns himself a date after surviving a formidable sparring session. Meanwhile, emotions run high as Travis’s jealousy over Vince’s relationship with Emily creates friction that threatens to derail the film completely.
As the chaos unfolds, Ari discovers the core of Travis's resentment: Vince's connection with Emily. He boldly interrupts a corporate meeting to reveal this truth, supported by Dana, who defends the film's quality. Just as it seems everything is falling apart, Ari decides to resign, using his severance to invest in Vince's project, ensuring its future.
In an inspiring turn of events, Hyde becomes a blockbuster success, grossing over $450 million globally. To top it all off, Drama secures a Golden Globe for Best Supporting Actor, capturing the moment with a jubilant shout of "VICTORY!!!"
Finally, in a delightful mid-credits scene, Ari fulfills his promise to give Lloyd away at his wedding, capturing the spirit of camaraderie as the group proposes creating a film or series based on their own adventurous lives.
