- Directors: Nicholas Stoller
- Producers: Judd Apatow, Shauna Robertson, Rodney Rothman
- Writers: Jason Segel
- Genres: Comedy, Drama, Romance
- Actors: Jason Segel, Kristen Bell, Mila Kunis, Russell Brand, Bill Hader, Paul Rudd, Liz Cackowski, Jonah Hill
Composer Peter Bretter (Jason Segel) has spent five years adoring his girlfriend, television star Sarah Marshall (Kristen Bell), despite living completely in her shadow. He even works as the composer for Sarah’s CSI-type crime drama, co-starring William Baldwin (as himself), Crime Scene: Scene of the Crime, a job that dramatically underutilizes his talents. One day, Sarah comes to Peter’s place after he’s had a shower to tell him she’s breaking up with him and there’s someone else. Peter tries to talk her out of it and goes as far as to refuse to put his clothes on, but it doesn’t work. Devastated, Peter impulsively starts having sex with random strangers, but he is still unable to overcome his grief. Upon advice from his stepbrother (Bill Hader), he decides to take a trip to Hawaii and stay at a resort Sarah once mentioned; when he goes there, he is confronted by Sarah and her new boyfriend, the articulate and narcissistic (though newly “straight edge” after a stint in rehab) British rocker, Aldous Snow (Russell Brand). The sympathetic receptionist, Rachel Jansen (Mila Kunis) bears witness to the awkward meeting and gives him an expensive suite on the condition that he cleans up after himself.
During the credits, a preview is shown for Sarah Marshall’s new show with Jason Bateman — a detective crime drama similar to her last one, called Animal Instincts, wherein she plays a detective who is also an animal psychic.