THERE is a lot to be gained these days by wearing your underpants over your trousers. It can give you super powers.

With bare hands you can lift up a sizeable portion of the Hollywood box office and hold it in the air for a whole summer. And millions of adults around the world will hold their popcornstuffed mouths open in awe. But for George Reeves, America's original Superman of the 1950s, the suit of red and blue worked liked Kryptonite on his career. It sapped him of his creative vitality;

casting agents stopped looking at him in wonder. The man who once floated on dreams of being a Hollywood leading man fell from the sky. So he unpeeled the suit and put a bullet in his head. The police report said it was suicide.

The year was 1959.

Hollywoodland is the first film by Sopranos director Allen Coulter and it contains a performance from Ben Affleck that won't save the universe, but might save his career.

Like Peter Bogdanovich's The Cat's Meow, it explores a disputed Hollywood death, but fails to land a knockout blow because the ending will always remain a mystery. Did Reeves really kill himself? Was he shot accidentally by his disenfranchised fiancée? Or more sinister still, murdered at the behest of a studio boss whose delicate wife Reeves had loved but left broken in pieces?

Hollywoodland is a film too of enigmatic parts that does not make a satisfactory whole. It rests in the shadows of noir, which gives it a seamy thematic edge, but it evades the genre's stylistic flourishes that give it bite. The smoky jazz soundtrack has to brood in the sharp daylight.

Adrien Brody's cynical detective Louis Simo looks too casual and baby-faced without a tie; and Brody plays him with a smugness that suggests he is busy giving caricature the slip. It isn't until he gets wrapped on the jaw with a chain that he smartens up his act and we start to believe he can do business.

A twin-track narrative flipflops from Brody in the present, working the puzzle, to Ben Affleck's Reeves in the past, working a glass of bourbon. He is stocky but sweet-tempered, a small-time actor who yearns for a piece of the big time. Diane Lane plays Toni Mannix, a former showgirl married to MGM vice president Eddie Mannix (Bob Hoskins). He's gruff and detached.

She needs love and attention - something Lane has coming to her after this fine performance.

She becomes Reeves's lover. She buys him a house and her husband doesn't mind - he keeps a Japanese mistress and he likes for all four of them to have dinner together.

Soon Reeves takes off with the lead role in a new TV series - Adventures of Superman. It makes him a national hero. Children revere him and drop everything to tune in. Ratings go through the roof.

But he is not content - television is the small time so he pushes for the bright lights of Hollywood. He gets a part in Fred Zinneman's From Here To Eternity.

In a neat camera trick, Coulter superimposes Affleck with the real Reeves in a scene alongside Burt Lancaster. Momentarily you pause and wonder: how would Affleck have fared among the vigorous standards of Hollywood 50 years ago? But then the camera cuts from the screen to a cinema audience. They snicker loudly: 'It's Superman!'. George Reeves has been typecast.

The real-life Reeves was more successful than this film allows.

The second world war did his career as much damage - the profile he had built up from a lead role in So Proudly We Hail! had been largely forgotten by the time he had finished his war service.

But why he was so unhappy with his portion of success is one of the themes Hollywoodland explores.

Why does celebrity, however small, only open a chasm of even greater yearning? The film casts a cynical eye on this town where everybody is on the make, but its conclusions are wispy like Los Angeles smog.

As George Reeves, Ben Affleck has earned much notice and a best actor award from Venice. For the role he gained weight and shed a lot of his vanity. Reeves was a man who pushed hard for very little. But Affleck has never been more than a lousy actor who gave little and pushed hard for much in return. His performance here, however graceful, only reminds us of the amount of deficits he has notched up in a career that has been given the full backing of Hollywood. George Reeves would say some get all the luck.