Salesmen Billy McMahon and Nick Campbell’s employer goes out of business, and Billy applies for Google internships on their behalf. They are accepted due to their unorthodox interview answers, despite a lack of relevant experience. They are the only interns not of traditional collegiate age. They will spend the summer competing in teams against other interns in a variety of tasks, and only the members of the winning team will be guaranteed jobs with Google. Billy and Nick are teamed with other interns seen as rejects: Stuart, who is usually engrossed in his smartphone; Yo-Yo, who was home-schooled by his tiger mother; and Neha, an enthusiast of nerd-related kink. The team leader Lyle constantly tries to act hip to hide his insecurities. Another intern, Graham, bullies Billy and Nick’s team. Roger Chetty, the head of the internship program, also expresses his doubts about the older men’s abilities. Stuart, Yo-Yo, and Neha see Billy and Nick as useless during a task focused on debugging and send them on a wild-goose chase for the fictional Charles Xavier at Stanford University. But later, during a game of quidditch against Graham’s team, Billy rallies his team to a comeback that unifies them as a team, despite ultimately losing after Graham cheats.
When the teams are tasked with developing an app, Billy and Nick convince the team to indulge in a wild night out. At a strip club, Neha admits to Billy that, despite her rich fantasy life, she has no real world experience and is nervous. With his support, she decides to stay. Nick gets Yo-Yo to break out of his shell by drinking and receiving lap dances. Encouraged by Billy, Lyle approaches one of the dancers, Marielena, who is also a dance instructor at Google on whom he had developed a crush. She is charmed by him, but another customer challenges Lyle for her attention and they fight, getting the team kicked out. Before sunrise, Stuart learns to appreciate his surroundings while overlooking the Golden Gate Bridge, and Lyle’s drunken antics inspire the team to create an app that guards against reckless phone usage while drunk. They win the task by earning the most downloads.
Meanwhile, Nick has been flirting with an executive, Dana, with little success. When he begins attending technical presentations to impress her, he develops an interest in the material. While the teams prepare to staff the technical support hotline, only Billy feels at a loss. A Google employee, “Headphones,” who always wears headphones and never socializes, approaches Billy and tells him that the way he interacts with people is special. He tutors Billy on the technical information. Dana agrees to go on a date with Nick, and she invites him in at the end of the evening. During the task, Billy is comfortable with the material, but his team receives no score because he failed to properly log his calls for review. Dejected, Billy leaves Google to pursue a new sales opportunity with his former boss. The final task is announced as a sales challenge. Teams must sign the largest possible company to begin advertising with Google. The team is stunned when Nick tells them that Billy has left, and they declare that they do not want to do the task without him. Nick convinces Billy to return, and Billy leads the team to show a local pizzeria owner how Google can help him interact with potential customers and thereby expand his business, while remaining true to his professional values.
Chetty is about to announce that Graham’s team have won, when Billy, Nick, and their team arrive to give a dynamic presentation about their new client. Chetty recognizes that although the pizzeria is not a large business, its potential is limitless because it is expanding via technology. Graham protests and is dressed down by Headphones, who turns out to be the head of Google Search. Nick and Billy’s team win the challenge and the guaranteed jobs. Graham berates his team, who finally reject him. As the students depart, Nick and Dana are still seeing each other, as are Lyle and Marielena. Stuart and Neha have formed a romantic connection as well with Stuart promising to see her in person rather than texting her, and Yo-Yo asserts himself to his mother. Billy and Nick toast their success.