Film Studies: Imagine asking Bogie to extinguish his smoke...

Edward R Murrow, the hero of Clooney's film and a saint to many liberals, was invariably equipped with a cigarette on camera as he calmly and persuasively argued the bombast and worse in Senator Joseph McCarthy. He was working less than 10 years after The Big Sleep and he smoked heavily. Two or three packs a day in the years when his pioneering investigative journalism had not yet picked up the evidence on the links between smoking and lung cancer. If you look through those books of stills celebrating movie-making, you will invariably find the great figures, their hands lowered, and holding a cigarette.

Murrow may even have reasoned that smoking looked worldly, sophisticated, attractive. I don't think there's any doubt but that the movies were a far subtler advertising for smoking than the very blunt come-ons - one of which usually ran with Murrow's television show. In films of a noirish tone or mood, cigarette smoke was a beautiful tracer for showing where the lights were; indeed, it was as much an element of décor in such films as the slatted imprint of venetian blinds or that overhang of shadow that attended Joan Crawford's brow. Good Night, and Good Luck was filmed in black and white in part so that kinescopes of McCarthy himself would look natural, but also as a kindness to the cigarette smoke.

But our base attitudes change very swiftly. I put myself in the place of a modern Californian child seeing the film. I think they'd notice the smoking before anything else, simply because today in California smoking has been outlawed from public places: in restaurants and theatres; at sports events in the open air; you can't even smoke in the expanses of Golden Gate Park. It follows that very few households know what smoking is. And the unwitting effect in Good Night, and Good Luck is that these people working in television seem afflicted, or handicapped. More than that, it makes the offices and studios of the CBS network seem like a place where body-snatchers have invaded. Indeed, the movie's required paranoia is perfectly embodied in the smoking. So smoke if you're a true American. And if you're not smoking, maybe you're a Red. Of course, there is evidence against this: McCarthy is the great non-smoker in the film, and Murrow did die of lung cancer.

This observation can be passed off as an amusing (or not) reflection on changing tastes in behavioural styles on film. But I think there's more to it. As ages shift, so we look for different clues when we examine people. Once upon a time, "everyone" smoked in movies and a lot of people wore hats. They also talked in sentences; they were shaved or well made-up; and they wore what must have been their characters' best clothes. All of which led up to the one essential thing: they were good-looking - no, more than that, they were beautiful. You didn't deserve to be in a movie unless you were beautiful, or unless your look had that dramatic emphasis, not quite the opposite of beautiful, but villainous. There was an equation between being good-looking and representing good that was idiotic and probably disastrous to our intelligence. Equally, wickedness was signalled by a variety of clues - excessive thin-ness; dandyism, razor-blade moustaches, sardonic expressions, whiplash insults delivered in perfect English (grammatical English has been suspect in America for decades). This is the code that numbered Basil Rathbone, Claude Rains and George Sanders as its disciples and regularly cast them in reliable villainy.

It would be nice to think that we are emerging from that orthodoxy, and that we know by now that people who look as dark, depressive and baleful as Abraham Lincoln may have a point to make, while a handsome, cheerful smile can lead us all to hell.

'Good Night, and Good Luck' closes the London Film Festival, 3 November, www.lff.org.uk, 020 7928 3232