Cops and robbers, robbers and cops. It's a classic genre, from children's games to cinema. And it's the spine of Christian Gudegast's directorial debut, the LA crime noir flick "Den of Thieves," where "cops and robbers" is writ so large it nearly becomes abstract. It's a film that wears its inspirations openly, with a whole lot of "Training Day," "Rampart," "The Usual Suspects" and "Inside Man" in the mix. With excellent cinematic craftsmanship and some clever twists, "Den of Thieves" just about places itself within that canon, even when it's too enamored of its own tricksiness.