The film begins with an episode of the TV series “American Success Story” documenting the lives of the main characters since the last movie. Lou Dorchen (Rob Corddry) has become a mogul with his Lougle empire and his side band Motley Lou. Nick Webber (Craig Robinson) has become a popular musician mainly because he’s made hit songs from the present before the actual artists could make it themselves. Lou’s son Jacob (Clark Duke) hates his father and doesn’t really want to be associated with him. Nick also mentions their buddy Adam Yates (John Cusack), who wrote a bestselling book and is currently going on a trip of self-discovery.
Nick is seen recording a music video for the song “Stay”, which he ripped off of Lisa Loeb and incorporated his own lyrics. The real Lisa Loeb works as his cat wrangler and mentions that the song feels personal to her. Nick quietly apologizes for stealing the song.
Lou joins his employees in the board room with his employees, all of whom are sick of his man-child schtick. One of the employees, Brad (Kumail Nanjiani), points out that the company is going down hard, but Lou doesn’t care. He brags about going making his success through time travel, while Brad retreats to the lab to find a way to save the company.
Lou hosts a big party that night in his mansion. He makes Jacob act as a butler. Jacob spots the pretty coat-check girl, Sophie (Bianca Haase), and tries to talk to her, yet she thinks he really is just a butler. At the bar, Nick and Lou are approached by an old schoolmate, Gary Winkle (Jason Jones), who is a total loser. He tries to convince Lou to buy a piece of land from him, which Lou declines. Nick also upsets his wife Courtney (Kellee Stewart) since she wanted to go to her sister’s home, but Nick always makes her go wherever he wants.
Moments later, Lou goes up the stairs and makes a big speech where he tells everyone to do things for themselves and to forget everyone else, to everyone’s dismay, including Lou’s wife Kelly (Collette Wolfe). The lights go out, and a gunshot rings out. Somebody has shot Lou in the dick. He tumbles down the stairs bleeding profusely. Nick and Jacob grab him and pull him up the stairs. Jacob pulls a switch shaped like a squirrel, taking the guys to the deck outside to reveal the hot tub time machine. Jacob grabs a vial of nitrotrinadium and puts it in the hot tub, setting it to send them back to stop Lou’s killer. Jacob also happens to spot Adam’s trench coat lying by the tub. They also get blackout drunk to set the mood properly.