Forgetting Sarah Marshall is the latest film from the Judd Apatow production team, which gave us Knocked Up and The 40 Year Old Virgin. They have reinvented the romantic comedy by taking the gross-out gags of male adolescent movies and mixing them with the soft emotions of the chick flick, creating the unisex romcom.

At their best, these films dig up the comic secrets in the sewer of the male psyche - but this one, written by its star, Jason Segel, is a dud. He plays Peter Bretter, a struggling musician who writes incidental music for a hit television cop show that stars his girlfriend, Sarah Marshall (Kristen Bell). Peter is a familiar figure: the sweet slacker who is half boy, half man. One afternoon, his true love turns up to break up with him. This most familiar of scenes is given a fresh twist by having the naked Peter refusing to put his clothes on. It’s a brave reversal of the usual practice of having a female actress naked, but it reveals nothing but Peter’s privates. The first-time director, Nicholas Stoller, quickly cuts away from Peter, so the scene never realises its potential for humiliation or humour. Anyway, Peter takes off for Hawaii, only to find Sarah with her new beau, a British rock star called Aldous Snow (Russell Brand). Tears and torment follow, until Peter finds romance in the arms of the lovely hotel receptionist, Rachel (Mila Kunis).

Having taken a long while to set up its premise, the film doesn’t know what to do next. Peter, tormented by Sarah’s presence, keeps weeping and is told by various people to get over it and move on. You wish the film would move on, too. Familiar Apatow actors such as Paul Rudd (as a goofy zen surfer) and Jonah Hill (as a starstruck waiter) turn up to lend some comic support, but not even they can pump up the energy and laugh quota.

That’s left to Russell Brand. I’ve heard that, as a comic performer, he is brilliant and charismatic. Something got lost in the move to the big screen, which is odd, as Stoller apparently told Brand: “Just be yourself.” Aldous is a character constructed out of the clichés of rock stardom. However, after this film, I suspect Brand will become the Hugh Grant of decadence - a safe, soft English star Americans can take to heart. He may steal the show, as many claim, but only because there’s not much of a show to steal.

15, 111 mins

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