Ron Shelton is a Yank director best known for competent but formulaic sports movies like Bull Durham and White Men Can’t Jump, and not generally thought of as the likeliest source of the next must-see movie. In Dark Blue though, an adaptation of the James Ellroy bulletstopper, Shelton has come up with the best action thriller of the year bar none.

Though apparently intended as a searing indictment of corruption, brutality and racism in the LAPD ranks, Dark Blue is far better consumed as a straightforward example of the cop/action genre at its very finest. Kurt Russell, often thought of as a name to avoid, uses the occasion to put in one of the most enormously enjoyable performances in the entirety of my living memory, playing (with much evident relish) a very bent LAPD cop with a bad alcohol problem, a propensity for excessive violence and a magnificent line in extreme right-wing and racist sentiment. (The whoring, degenerate scuzz-pig depicted in Irvine Welsh’s Filth leaps to mind by way of comparison – but doesn’t come close.)

It’s set in LA at the time of the trial of the officers who laid waste to Rodney King, with racial tensions massively on the increase and the riots about to start. Meanwhile, Russell and his beleaguered colleagues on the force are facing an internal investigation over their use of lethal force against a suspect. A virtuous black cop (Ving Rhames) doesn’t believe a word of the other cops’ testimony, but Russell and pals would seem to be in the clear thanks to the protection of a sinister police chief (Brendan Gleeson).

Russell is a pure joy to behold, an unbelievable walking tornado of politically incorrect angry white male Americanism on legs, routinely leaping out of his car to line entire gangs of innocent black youths up against walls, and offering a constant supply of foul-mouthed but very funny right-wing rants against the state of his once-proud nation. (He reacts to his son’s habit of phoning “slut lines” with the relieved, proud and affectionate observation that “at least he ain’t a fag; the kid’s finding his dick”.)

Gleeson, too, is in supreme form, effortlessly managing to convince (he looks exactly like a cop), and if Dark Blue has very minor plausibility flaws from time to time, it’s still near-requisite viewing for anyone with a pulse. Leaving even the recent Narc in the shade for pure blood-pressure impact, this is the thriller of the year.