To mock Sienna Miller for playing a ditzy star in Steve Buscemi's Interview, thus playing out her own tabloid reputation on screen, would not be a good idea. She is actually much better than you might expect in this tribute to the film of the same name by Theo Van Gogh, the radical Dutch film-maker murdered by an Islamist terrorist in 2004.

Miller may have been typecast as soap star Katya, but she proves she can hold her own against as fine an actor as Buscemi, who plays Pierre, a political journalist furious at being sent to interview her. It's a portrait of which she can be justly proud, light years ahead of anything she has so far achieved in the cinema.

This is virtually a two-hander and it's stretched a bit, even at 84 minutes. Van Gogh found the characters despicable but Buscemi, as director and writer as well as actor, renders them rather more sympathetically.

Pierre sits in the restaurant waiting for her to arrive for an hour before she enters, and begins complaining that she hasn't got her usual table. This makes him the more irritable and he makes it clear that he hasn't seen any of her work and doesn't want to. Added to that, there's a political storm brewing in Washington that he'd rather be covering.

Understandably, she flounces out, but later sees him groggy in a taxi that has crashed (largely because the driver has spotted her on the pavement), and takes him home for repairs. The two then circle round each other, inviting disrespect but perhaps wanting each other as well.

For her, he ought to be like all the other men who want to get her into bed. For him, she may be desirable but any move on her would be tantamount to defeat.

The result is a cautious exchange of secrets it would be unfair to give away and a conclusion in which Katya has a victory of a sort over the supposedly greater intelligence and sophistication of her interviewer.

Buscemi's usual hangdog air covers but doesn't hide his skill as an actor, and his portrayal of a man near the end of his tether is cleverly contrasted with Miller's portrait of a young woman living in the glare of the fame she clearly wants but finds as hard to bear as to enjoy.

Interview is well-made but depends almost entirely on its acting. Neither of the two principals let it down, even when the screenplay isn't quite as sharp as it could have been.