Somewhere along the way, the words “Judd Apatow” on a production’s credits stopped being an unqualified positive. The Apatow thumbprint is a guarantee of a certain brand of uproarious adult smut; rom-coms in which the blokes are incorrigible overgrown babies who suck on a bong instead of a pacifier and the girls are humourless hot chicks. The formula was always going to get stale. And with the flabby, underseasoned Forgetting Sarah Marshall, it just did.

Produced by Apatow, the film is written by and stars Jason Segel, an actor cast from the same slightly doughy Everyman schlub mould as Seth Rogan. Segel plays ordinary guy Peter, a musician whose career has stalled to the extent that he now writes ominous chord progressions to accompany shots of corpses in a cheesy detective show. Peter has a girlfriend he worships – Sarah Marshall (Kristen Bell) is the star of the TV show he works on. Early in the story she dumps him in one of the film’s most creatively humiliating moments (of which there are several).

Nursing his heartbreak, Peter takes a holiday alone in Hawaii, only to discover that Sarah is staying in the same hotel with her new beau, British rock star lothario Aldous Snow (Russell Brand, effectively loathsome). Distraught that his ex is now in the arms of a man who is a cross between Mick Jagger and the hair you find down the plughole of a bath, Peter turns to drink. Fortunately he is such a likeable guy that he is soon the best of buddies with the resort employees, including the unfeasibly pretty Rachel (Mila Kunis). Not only that, Sarah starts to miss him.

It’s amusing enough, but beneath the self-deprecating loser comedy is a calculated piece of revenge fantasy. There is only one side to this story, and it’s Peter’s. Poor Sarah may be vain and shallow, but she put up with a cereal-scoffing stoner for five years. Doesn’t she deserve some sympathy?

15, 110mins

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