Still, Ayer is nothing if not a dogged, determined sort and he's back on the warzone-like streets of South Central Los Angeles for his latest, far more accomplished outing.
This time out we're not dealing with corruption and power-grabs but we are placed in the back of a black-and-white police vehicle as uniformed officers Brian Taylor (Jake Gyllenhaal) and Mike Zavala (Michael Pena) go about their business.
Granted, the pair have a knack of upsetting their superiors by developing a nose for trouble rather than handing out tickets for misdemeanours, but they're essentially good cops and clearly great friends.
In fact, the rapport between Gyllenhaal and Pena is crucial to drawing the viewer into End of Watch.
Its largely episodic nature and the director's leaning towards almost but not-quite making the film the latest addition to the 'found footage' genre may prove a stumbling block to some.
Having negotiated car chases, had fist-fights with suspects, witnessed how crack addicts treat their kids and responded to a house fire, Taylor and Zavala accidentally uncover a large drugs haul and find themselves on the radar of a ruthless Mexican drugs cartel, which is where the movie finds its major riff in the final third and Ayer moves to a more conventional style.
End of Watch is a violent and undeniably exciting film, with a great double-act from Gyllenhaal and Pena at its centre and yet another fine performance from Anna Kendrick in the underwritten role of Taylor's girlfriend.
It feels all too real and its depiction of the clearly unwinnable war against crime and drugs would lead me to guess that it won't be topping any 'best-of 2012' lists in the mayor of Los Angeles' office.
It could well be featuring in mine, though. HHHHI
SILVER LININGS PLAYBOOK Romantic drama. Starring Bradley Cooper, Jennifer Lawrence, Robert De Niro, Jacki Weaver, Chris Tucker, Julia Styles. Directed by David O Russell. Cert 15A
David O Russell is a difficult director to get a handle on. Three Kings was a gripping, stylistically dazzling story, while his last movie The Fighter hit home on every level.
Crucially, while Russell wrote the screenplays those stories came from other sources as, when he's left to his own devices -- as on Flirting with Disaster and the irredeemably annoying I Heart Huckabees -- the results can be patchy at best.
Adapted from a novel which was a best-seller in the States, Silver Linings Playbook is a curious beast of a film. We initially see Patrick (Bradley Cooper) being discharged from a mental institution in Baltimore and returning home to Philadelphia.
Clearly still not right, his fretful parents (Robert De Niro and Jacki Weaver) try to put up with his occasionally explosive behaviour as he deludes himself that he can possibly be reconciled with his wife following 'the incident' which led to him being sectioned in the first place.
At this stage you're wondering whether Russell is going down a very wrong road of portraying mental illness as being nothing more than a quirky plot device, a fear hardly allayed when we see Patrick's father's foibles, and deepened when Patrick is introduced to Tiffany (Jennifer Lawrence).
A cop's widow and clearly carrying plenty of emotional baggage of her own, Tiffany is direct and abrasive but the pair eventually form a bond, although his motives for doing so play against the conventions of romantic drama.
And speaking of conventions, the movie's final third heads towards a set-up which is so traditional it's almost beyond cliche but, somehow, Russell manages to pull it all together and give us the kind of ending the start of the movie never even hinted at.
That he could do so is totally down to the quality of the acting. Cooper is great as Patrick, De Niro and Weaver superb as his parents but the movie could easily have collapsed were it not for the truly outstanding performance of Lawrence.
Her Tiffany is the glue that holds everything together here, breathing life and depth into a character which could, in lesser hands, have been a manic, needy cipher. It's Jennifer Lawrence's movie and, I suspect, Jennifer Lawrence's Oscar. HHHHI
GAMBIT Comedy. Starring Colin Firth, Cameron Diaz, Alan Rickman, Stanley Tucci, Tom Courtney. Directed by Michael Hoffman. Cert 12A
With a script by the Coen brothers, a top-class cast and a solid director, what could possibly go wrong with a remake of the 1966 caper movie which gave Michael Caine his first major Hollywood role?
Where would you like to start?
From the sub-Pink Panther titles which actually reveal most of the key plot points, Gambit is a total disaster for all involved.
The story of how a put-upon art curator (Colin Firth) plans to swindle his tyrannical boss (Alan Rickman) with a Monet forgery, with the assistance of a Texas rodeo queen (Cameron Diaz) beggars belief, as does the laugh-free script, much of which involves the unfortunate Mr Firth misplacing his trousers.
Honestly, this film is so bad you actually end up feeling sorry for the cast as they have to plough through material which wouldn't have passed muster on a mid-period Carry On. Awful. HIIII