The latest film from the writer of Training Day is pushing a bold and novel premise on a sceptical world – hero cops. Not free wheeling deductive killing machines that are cops in badge only, but genuine, protect and serve, beat patrolling, law enforcers.

It would be an odd notion in any US city but on the mean streets of LA it is absurd almost to the point of subversion. The LAPD is bent; they are all venal corrupt bigoted pigs: everybody from James Ellroy to Stan and Ollie says so. Taylor and Zavala are two good apples aiming to spoil their otherwise wholly sullied reputation by doing the job with pride and conviction.

It takes a bit of getting used to. It isn't until they rescue children from a burning house that it really sinks in that they aren't going to beat up people for fun or make off with drugs from a bust. They are a hardened pair but not jaded and Jake Gyllenhall and Michael Pena give them an easy natural bantering relationship. Their daily beat though is hellish. It's The Bill with severed heads, human trafficking and shoot outs.

The script is staged as a day-to-day life on the beat procedural but around that the script stitches in a slowly growing plot. As in The Shield, the film suggests that African American gang violence is being superseded by the ferocious savagery of Mexican cartels.

At the start the film drums up a found footage angle with Gyllenhaal camcording everything for some not very convincing reason, but it isn't married to it. The film mixes in uses the handheld footage to generate an intense realism and provide a fresh look for the LA sprawl which has been filmed so extensively it is exhausted visually. The movie is kick started by a bold opening car chase sequence shot entirely from a camera fixed to the front bonnet that immediately has viewers straightening in their chairs in the expectation of something a cut above the norm.

And having raised expectations, it delivers on them. End of Watch isn't free of Hollywood cop movie compromises but is still a remarkable and unusual ride.

END OF WATCH (15)

Director: David Ayer

Starring Jake Gyllenhaal, Michael Pena, Anna Hendricks, America Ferrera, David Harbour and Frank Grillo Length: 108 mins

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