Writer-director David Ayer has certainly found his groove - gritty crime thrillers about morally tainted cops who bend the law to compensate for an imperfect legal system - but he's in danger of getting stuck in it.

Having previously penned screenplays for Training Day, Dark Blue and Harsh Times, making his debut behind the camera with the last film, Ayer returns to the crime-infected streets of Los Angeles with this brutal journey into the city's underbelly.

Renowned novelist James Ellroy (L.A. Confidential) provides the creative spark for the script, co-written by Kurt Wimmer and Jamie Moss.

However, the set-up and its bloody pay-off are all familiar, even down to the fractious relationship between Forest Whitaker's corrupt mentor and Keanu Reeves' sharp-shooting protege.

The hard-boiled dialogue is suitably snappy ("Do the department a favour and wash your mouth out with buckshot!") but fails to draw blood in the hands of a cast whose imposing physical presence dwarfs any acting prowess.

Oscar-winner Whitaker relishes his role as the biggest, baddest apple on the top of a rotten barrel, but even his eye-catching performance is table-thumping fury without the emotional firepower.

Street Kings revolves around veteran police Detective Tom Ludlow (Reeves), who is still reeling from the death of his wife, numbing the pain with regular swigs of vodka.

Tom is at the beck and call of his commanding officer, Captain Jack Wander (Whitaker), often going undercover to infiltrate crime syndicates then taking the bad guys down with extreme force.

He rarely plays by the rules, making him a prime target for Captain James Biggs (Laurie) and his colleagues in Internal Affairs, who must question the moral shades of grey in the department.

Ludlow's colleagues in the specialised Ad Vice unit begrudgingly cover for him because results make them all look good.

However, their patience is wearing thin.

In the aftermath of a shout-out, Tom learns that his former partner Detective Terrence Washington (Crews) is planning to rat him out to Biggs.

Soon after, Tom is embroiled in a grocery store hold-up in which Washington is brutally slain and he, rather conveniently, survives unscathed.

Street Kings is an amalgam of Ayers' earlier films, sparking momentarily to life in the heated exchanges between Reeves and Whitaker.

"What happened to just locking up bad people?" asks Tom. "We're all bad people Tom," replies Captain Wander, stating the obvious.

Laurie's performance is a shadow of his eccentric medic on the hit television series House, manipulating events by planting the seeds of suspicion in Tom's mind.

Action sequences are competent if uninspired, culminating in a showdown that sees one member of cast being hand-cuffed to the scenery to prevent him chewing it.