Peter Bretter (Jason Segel) is a composer who makes his living creating the music for a popular crime television series, and he thinks he is happy, especially as the equally popular star of the show, Sarah Marshall (Kristen Bell), is his girlfriend. Although he's something of a slob, he is content until Sarah walks into his apartment one morning after some time away and breaks some bad news to him: she doesn't want to be in a relationship with him anymore. Peter is stunned, but knows by the look on her face she is serious, and not even a final hug will change her mind. So now what?
Forgetting Sarah Marshall was one of the comedies to emerge from the Judd Apatow stable of talent, and the first major big screen role for Segel, whose profile had risen when he was part of the ensemble of Apatow's cult TV series Freaks and Geeks. Here he was playing a similar character to the one he had there, unlucky in love, unaware of his limitations until it's too late, and interested in making music his career, although Peter had succeeded in that respect, even if he realises early on that crafting the ominous tunes for some CSI-style effort is not what he really wants to be doing with his life. It takes the absence of Sarah to wake him up.
Segel also wrote the script for this, and evidently was conjuring up something he knew would play to his strengths as a performer, even if that persona risked alienating the audience, for the first hour at least. Peter is something of a pathetic soul, and while he doesn't quite cross the line into creepy obsessive, it's a close run thing, so when he decides that a holiday in Hawaii is what he needs the not exactly surprising twist does little to endear him to us. That's right, the minute he arrives at the hotel he bumps into Sarah, who happens to be beginning her vacation at the same location - he should have guessed before he made his plans.
Also along for the ride is Sarah's new boyfriend, a louche British rock star called Aldous Snow, played by louche British comedian Russell Brand. Actually, Brand was pretty much playing himself, with music standing in for comedy as his career, and he won some decent notices for his role, mainly among those who hadn't been overexposed to his shtick which was growing overfamiliar to many people by this stage. Didn't stop him being successful, and that hold Aldous has over the other characters worked out well for the film, particularly as we're meant to be in full sympathy with the hapless Peter.
If you can get over the strong whiff of needy desperation that he carries with him, something that the receptionist at the hotel's front desk finds all too easy to do. In one of those only in the movies plot developments, or only in the movies written by the star that is, she falls for Peter by first feeling sorry for him and then getting to like his "poor me" personality, so naturally this Rachel character is essayed by the most beautiful woman in the film, Mila Kunis. Rachel has her darker side, of course, but this seems to be a sop to those who resist the customary improving female who turns up all the time in movies like this, and shouldn't detain you for long. To the story's benefit, Segel didn't make the path of true love run smooth, and what could have been a bitter trawl through his own personal breakups, as if to get his own back, is admirably able to see both sides of the argument. It's just a pity that this diverted him away from the more promising jokes. Music by Lyle Workman.