Directed by Joe Carnahan starring Jason Patric and Ray Liotta

While most praised Sylvester Stallone for punching above his weight as the duped sheriff in 'Copland', for some the real star of the film was Ray Liotta. Having spent his post 'Goodfellas' years in rental fodder like 'Corrina, Corrina', 'Turbulence' and 'Operation Dumbo Drop', Liotta's turn as the sweaty, overweight and coked-up detective Finch dominated scenes and provided the film's most intriguing character. And with 'Narc' he's at it again, putting on the pounds and turning in a great performance as another compromised cop who could have a lot to hide.

Suspended and burnt-out following a fatal shooting while on an undercover assignment, detective Nick Tellis (Patric) is offered a way back in to the force if he'll work on the unsolved murder of a drug squad officer. Tellis agrees, but his new role pairs him with Lt Henry Oak (Liotta), a close friend of the slain policeman who was also working as back-up on the day of his death. From the outset there's electricity between them as Oak's brand of instant justice clashes with Tellis' low(er) key approach and the deeper they get into the case, the more each man wonders how much the other really knows.

As the strung-out lawman in 1991's 'Rush' Patric also showed what he can do with a badge and some demons and his partnership with Liotta is one of the most unlikely yet satisfying detective double acts in years. From its harrowing opening, right through to the shocking finale, 'Narc' is bleak and relentless but fans of police dramas from both TV and the 70s shouldn't miss it. Director Carnahan - who also wrote the script - finds the right mix of procedure and predicament as Tellis and Oak scour the streets of Detroit only to find that their clues lead right back to the force they're part of.

What makes the film unusual is the absence of real hero characters. As Tellis, Patric has the advantage over Liotta, but the fact that the two detectives have let their personal lives become drowned out by crime makes you wonder if you could bet on either of them to do the right thing. Liotta eats up the scenes, whacking a wife beater with a cue ball in a sock, warning Tellis not to get in his way and charging through every door shotgun first.

Trapped between admiration and suspicion for the older man, Patric's character gets slowly swallowed up again into a job that nearly killed him 18 months before and his desire to solve the case becomes a way of redemption from his past mistakes. You'll think you've spotted the ending from a long way off but just when you're convinced the evidence is air tight, Carnahan twists the whole story, leaving you with this ache of regret that the mismatched duo didn't have more faith in each other from the start.

'Narc' was made for just $5m - if there is any justice it deserves to earn15 times that.

Harry Guerin