Film: Also showing: The survival of the least interesting

Wild Wild West (12) Barry Sonnenfeld; 106 mins Another Day In Paradise(18) Larry Clark; 101 mins

Whenever an adventure film goes wrong and everybody hates it, the director heaves round and claims it was intended for children, and didn't we all know that that was the case, and how could we have possibly missed the fact? George Lucas did it with his latest Star Wars.

Liar! He knows that the people having their toy light-sabres framed and mounted and doing their nut trying to book more than 12 tickets in advance are not children. Yet, having apparently abandoned his adult audience, Lucas seems content to bore our sons and daughters to death. "Children's cinema" - the last refuge of the sonorous fake.

In Wild Wild West, Will Smith stars as Jim West, a post-Civil War federal agent. Smith is America's favourite omnicompetent star at the moment. He tiptoes through his films, and sings his hip-hoppy songs ("Any damsel in distress will be out of that dress when she meets Jim West") and turns up to premieres smiling plushly, his wife gazing up at him like an astonished little dolly. It's survival of the least interesting.

Will Smith and the director, Barry Sonnenfeld, made a fortune with their last film, Men in Black, a superbly subversive sci-fi comedy which suggested that all the headlines in the National Enquirer were true. This time, Smith hooks up with a US marshal, played by Kevin Kline (what happened to all the off-Broadway Chekhov, Kevin?). The pair are ordered to combat the mean Dr Ariliss Loveless (Kenneth Branagh) who wants to bring down the government in revenge for losing his legs as a Confederate soldier.

Kidnapping the world's finest scientists, Loveless also builds a massive mechanical spider, which shoots fire like a tripod. Branagh sits inside, looking as cross as he probably is in real life, his hair dyed to death, his flag pseudo-Nazi, his henchpeople terrifying Austrian-ish women with plaited hair.

Wild Wild West is precisely the kind of film that lobotomises itself the faster and louder it gets. It is full of the standard phrases that denote enthusiasm, and the standard tones of semi-involved enjoyment. It has endlessly repetitive routines, the sudden manoeuvres of the unsure, the power surges of the intellectually idle.

Sonnenfeld is in a total panic, trying to divert us from rumbling that there is no script. He has Smith and Kline jumping on and off their racing- green steam train like maniacs. The film is discomfited by its technology. The more literal the mechanics Sonnenfeld employs, the weaker he seems, desperately calling Loveless's machine a "weapon of mass destruction", like someone brain-washed by CNN. This machine, raised-up and angry, gets lots of screen-time, but Sonnenfeld seems more at home when his heroes are on their steam train. Happy though he is to exploit special effects, he is still secretly affiliated to the old school - he only really knows where he is when sitting under a luggage rack, drinking gin and tonic out of a little can.

But the worst thing about Wild Wild West is that it's tedious. You will cast round for a sweet wrapper to read. Or you might fight off sleep by trying to list the many different ways West is promoted as a morally bionic hero. He's not just a black man, but an ex-slave. An ex-slave whose relatives were killed in a massacre. An ex-slave whose relatives were killed in a massacre, who was then raised by Indians in the desert. It's amazing that he can get both himself and his halo on his horse.

You begin to wonder if Smith actually is bionic. His eyes have the glaze of crockery and sometimes the light catches them and you imagine something digital behind. When he looks the same at 50, only you and I will know why.

Larry Clark's Another Day in Paradise is his second film. His first, Kids (1995), charted a day in the life of a New York teenage gang: one in the group liked to seduce virgins, knowing he was HIV positive. Kids culminated in the rape of an unconscious girl at a party. Clark combated the furore that attended its release with the cry "This is how it is! This is real!", not recognising that the torpidity of the film felt so much more his than its characters.

Another Day in Paradise is less carping, more alive, and almost successful. Set in the American Mid-west in the 1970s, it stars Melanie Griffiths and James Woods as long-time heroin addicts and thieves. They hook up with a teenage couple, Bobbie and Rosie (Vincent Kartheiser and Natasha Gregson Wagner), also addicts and nickel-and-dime heisters, but as yet only young in deed. The group heads off on the promise of a big score, and in between ferocious fights and the odd murder, they emerge as a kind of family.

It's really Clark's casting that triumphs. Kartheiser is a ragged child, the hair above his pubic bone new and shy, his skin so pale it looks utterly ruined by just the one spot, the one bruise, a burgeoning scar. Woods is familiarly hostile - a flurry of complications, clever and creepy, with a face that looks almost mouldy with its pockmarks.

But it is Griffiths who is really thrilling. Although she persists with that fawning voice that makes her sound like a pet with no status, she is certain here, glamorous beneath her over-done eyes and tetchy fringe. You buy her as a woman, pragmatic but wasted, conspicuous and old before she can handle it.

If there is art in the performances, there is little from Clark, but his final frame is memorable. Bobbie escapes across a corn field, his girlfriend dead, his emotional territory diminished, his trousers shapeless with wear. Realising he is free, he sends up a cry of delight, and Clark follows that cry, high in to the air, as though it carried this child's whole potential, intact and still precious. The credits roll, but you're too touched to notice.