Bob Crane is always going on about what a likable guy he is. Well, he may be polite and he may have a bland charm that appeals to housewives and poindexters, but can a man who cheats on two wives and ruins two marriages really be classed as likable?

And Bob Crane also goes on about how normal he is. Well, yes, sex is normal and knocking about is hardly immoral, but this is a married man with children who is sleeping around. And not only that but he's a man who doesn't seem to see anything wrong with his behaviour. Apparently everyone else has the problem. But he's also a man who tapes his sex sessions (sometimes illicitly) and who watches them with his best buddy. Likable and normal he most certainly isn't.

What comes through strongest in Auto Focus is the strange homoerotic relationship that exists between Bob Crane (Greg Kinnear) and John Carpenter (Willem Dafoe). It's kind of a perverse love story. In the first scene they share, John almost serenades Bob. It's love at first sight. Then pretty soon afterwards they're scoring chicks, banging beaver and filming their exploits.

In fact, the two characters kind of complete one another. At the beginning Bob is curious but kind of naive – he has 'photography' magazines and is almost embarrassed when he goes to his first strip joint – while John is horny and self-assured, but, being a mere mortal, can hardly be guaranteed to score every time. So when the bumbling Bob and the confident John hook up, they make a pretty good partnership.

And at the beginning things go well. With Bob's celebrity and John's photographic equipment and electronic gadgets, they're bagging chicks and having fun. And at the start things are relatively tame – after years of dull marital sex, Bob is excited merely at the prospect of doing it with the lights on. But as things progress, the relationship between the two men gets more and more perverse. The first hint that this is more than mere macho tag-team screwing is the way they talk as they watch their tapes. John says to Bob, "Where have you been all my life?" While Bob says to John, "It's either him or me" (Bob doesn't like one of John's other customers - one of Bob's co-stars in 'Hogan's Heroes' - and wants John to choose between the two of them). This isn't a mere friendship.

Then there's the way that Bob gets outraged when he sees, via tape, that during an orgy, John has had his hand on his arse. When you're filming sex tapes with your best buddy and watching them together, it seems rather churlish to complain about getting your bum groped.

But although they have a bit of a lover's tiff over this, the pair soon hook back up again. And then, in an extraordinary scene, they watch another one of their tapes. At the time, Bob is saying how much he misses his wife and child. But immediately afterwards, he and his best buddy begin masturbating as they watch one of their recordings. And then as they're abusing themselves, they begin to debate who the woman is and where it was filmed. To them, this is completely normal. It's ordinary. No wonder neither is capable of maintaining a healthy relationship – they've chosen the surface (photography and sex tapes) over anything with real meaning. The focus truly is on themselves. To hell with the subtle pleasures of a loving relationship; everything here is focused on orgasm.

But that's one of the conundrums that Auto Focus presents. Where you're famous and when women are lining up to have sex with you (fame is the world's best lubricant), how can you be expected to exercise self-control? Surely that's every man's dream. Well, it probably is the dream of most men, and it can hardly be a surprise that Crane cheated on his wives, but what makes him so extraordinary is how completely lacking he is in self-awareness. He talks to priests, Christian magazines and his agent, seemingly sincere in the lies he spews ("I'm a one woman man." "Bob Crane is a good guy." "I'm normal."). He really does think that his wives are being unreasonable in expecting him to be true to them. He really does think that keeping an album of the women he's slept with, and showing it to other people, is okay. He really does think that there's nothing strange in watching sex tapes with his best buddy and wanking himself off as he contemplates the peculiar way that the female mind works. His life is evidence of what happens when a shallow man with little intelligence is given fame.

But although the character is shallow, Greg Kinnear's performance is complex. He really doesn't a put a foot wrong. He's got the easy charm and wide-eyed confusion down pat. He plays Bob as a man who is always sincere, who is always polite and charming, but who is constantly hurting those around him. And his performance is also incredibly seedy. I particularly like the way he leers at his son's girlfriend. The man has no self-control; no idea of social mores. And there's a great piece of acting when he gets a barman to put 'Hogan's Heroes' on so that he can pick up a couple of women. He feigns surprise so well when one of the women asks him whether he's the man off the show that I wouldn't be surprised if Crane fooled himself into thinking that he didn't in any way manipulate these women when he was picking them up.

I also like scene when he receives a call from Disney. They want him for a film called 'Superdad'. The way that he juggles sleaze and respectability is impeccable – right before the call he talks to John about making a sex movie, and then he shows John his penis. Yep, that's 'Superdad'.

But ultimately it's quite a sad film. Crane's death, being beaten while asleep, is both brutal and pathetic. Yes Crane wasn't a good man, nor was he a normal one, but you can't truly call him a bad man either. He certainly wasn't vindictive. He was just a sad, seedy little man who died a sad, seedy little death. His crime was being clueless, stupid and far too horny.