Steve Martin was seriously funny, but now he's sappily serious. So who do we blame? Rollins and Joffe, that's who.
"I will be decidedly ... unfunny," promises the hero of A Simple Twist of Fate. The role is played by Steve Martin, once a contender for the title of funniest man alive. Martin's character keeps his word, as he attempts to gain custody of a baby girl left abandoned during a storm in which his life-savings are snatched by the girl's father - who is on the run after leaving the mother dead in a car crash. It is not a laugh- riot.

But then these days Martin's fans would be surprised if it was. In recent times, they've had to suffer the self-styled Wild and Crazy Guy being a humbled con-man in Leap of Faith, and, in Grand Canyon, a Joel Silver- like producer crippled by a bullet in the leg. Nor is Martin alone. Of his most talented comedy rivals, Robin Williams these days seems happiest musing on the joys of fatherhood in Mrs Doubtfire, Hook and the upcoming Nine Months. Like Williams, Billy Crystal seems no longer happy to go straight for the comedy jugular, preferring instead to play amusing characters with big hearts and deep emotions (cf his trip around the male menopause in two City Slickers and a maudlin old age in Mr Saturday Night).

There's nothing new in comedians wanting to crack rounded characters rather than a series of jokes. But until recently, you could at least count on them to make you laugh, too. Time was when a comedy star's career was usually over before he had time to explore his inner recesses. Like popstars, movie comics have traditionally had a short shelf-life. From the Marx Brothers to the Police Academy, no-one's shtick has stayed fresh for long.

It was Woody Allen who first broke through this barrier, with Annie Hall. But it was the shadowy men behind Allen who were the original architects of the trend for "mature" comedy which followed: his managers, Jack Rollins and Charles Joffe. Movie moguls in their own right, the pair are noted for significantly influencing their clients' stylistic output and for taking a cut from every project Allen commits to celluloid. In fact, it was Allen who first approached Rollins and Joffe in the Sixties, offering his services as a gag writer to another R&J client, screenwriter / stand- up comedienne Elaine May. They converted Allen from an unassuming comedy writer into the Bergmanesque auteur we put up with today.

First turning him into a stand-up, they insisted he work on his "point of view". Subsequent clients, including Robin Williams and Billy Crystal, were given similar advice. Crystal was encouraged to think about "what I felt about daytime TV". Williams was asked to develop an unfunny monologue about an old man feeding pigeons after the Bomb. Martin had different managers, but at some point he was fed a similar line. His second attempt at a film with a "point of view," LA Story, seemed in part to be modelled on Annie Hall. He had always wanted, he said, to do "a movie with a story and emotions". This was his excuse for remaking Father of the Bride, distinctive for its almost total lack of either "story" or "emotions".

It hasn't all been bad. Martin, in particular, has done "mature comedy" worth watching (Roxanne and LA Story to name two). But there is little in these later movies to match the gag-a-minute heights of his early work.

And even if Martin, Allen, Williams and Crystal do make a return to "the early, funny ones", they may find that the genre they once helped to shape no longer has a place for them. Comedy these days is more likely to be found in the ironic one-liners of the action movie than in the latest Dan Aykroyd. The line of films starring people who just wanted to make you laugh now seems to have died out. Even Jim Carrey, whose physical humour and freewheeling idiocy nostalgically suggest Martin, has started talking about the art of "character". A close look at his cv reveals that, in his formative years, he was managed by... Rollins and Joffe. The last laugh may be just around the corner.

n `Simple Twist of Fate' is on general release