Jodie Foster is a specialist at playing wounded women. And she gets her chance in spades here as Erica, host of a radio show called Streetwalk whose impending marriage to fiancé David (Naveen Andrews) is wrecked when violent muggers kill him and injure her in Central Park. Now the city streets she loved to roam appear strange and threatening. She buys a handgun to protect herself, and finds herself using it to kill.

Irish director Neil Jordan's handsomely directed film, made in America with all the trimmings of a smart Hollywood movie, then puts Erica in front of a series of desperate situations which suggest that either she is unlucky or that the film has taken leave of its logical senses. Those who thought Mayor Guiliani had cleaned up the city of New York are obviously wrong.

First there are more muggers on the train, then a violent convenience store hold-up. A third incident involves a pervert indulging in child prostitution. On each occasion she uses her handgun to good effect and runs off into the night. She now hardly recognises herself and half-hates what she has become. Thus, the film suggests, are vigilantes made.

Jordan tries hard to elevate this thriller above something like Death Wish, not only by the skill of his film-making, but by making it clear that we may be sympathetic but are not supposed to approve.

We see that the police, headed by Terrence Howard's decent but seemingly impotent detective, are unable to cope with Erica's initial tragedy. Nor can they link the multiple murders, even though the detective gets to know Erica and even appears on her radio show.

It isn't giving much away to say that Erica finally catches up with those she is pursuing, though once again logic would seem strained at the way she does so. What's worse, the film's finale is so morally ambivalent that it almost hints at a feelgood rewrite to help audiences through. The film, in fact, gets less and less authentic as it progresses, however well its detail is deployed.

What you can't deny is Foster's expertise at mixing vulnerability with an inner rage that half excuses what she is doing. It's an intense, bloodied up performance, matched by Howard's immaculate portrait of the detective whose warm relationship with Erica is only matched by his determination to uphold the law.

But, try as he does to make this more than just another vigilante movie, Jordan is hoist by the petard of a plot that badly wants to have it both ways. Perhaps he should go back to writing his own material.