Unfortunately for Ayer, his emphasis on ritualistic, gruesome violence is the only thing believable about his ill-conceived picture. Simultaneously clichéd and monotonous, Ayer's film is only convincing when it’s trained on chest-thumping, sociopathic behavior. But even when the sociopaths in question are cops, the characters played by the atypically threatening Jake Gyllenhaal and Michael Peña never feel like their behavior is so dangerous or so sophomorically vile that it’s unjustifiable. Ayer likes his monsters too much to really do much with them beyond show how potentially dangerous they are and then valorize them for unwittingly not crossing a line and becoming full-on thugs with badges.
Gyllenhaal and Peña respectively play Brian Taylor and Mike “Zee” Zavala. Brian and Zee spend much of the film going on patrol, talking shit to each other and half-assedly realizing the limits of their own mortality with each new bust they make and brawl they reflexively instigate. As a two-man unit, these guys are, however, most convincing when they’re shooting the shit aimlessly and making fun of each other for basically conforming to ethnic stereotypes. Being Mexican, Zee has a big family and values his wife’s physical presence more than her ideas. Brian is relatively more nebulously defined via caricature. He’s going to grad school and studying film, hence his tentatively explored interest (at best) in documenting his life as a modern-day lawman. A former Marine, Brian has a lot of quick flings but has yet to find the right woman for him, someone that he can talk, to until he meets Janet (Anna Kendrick).
Janet is almost never defined by her ideas, but again, this is mostly because Ayer never defines his characters beyond a point. Ayer does admittedly try to show that there is in fact a world of police officers and social protocols that exist beyond Brian and Zee’s tendency to pursue whatever cases they feel they should. But a scene like the one where an unnamed officer bluntly expresses resentment at how pampered Brian and Zee are goes nowhere. Likewise, many of the other officers, especially the women officers that flit around Brian and Zee but never establish their identity beyond being simultaneously butch and sassy, are too vague to be truly sympathetic. Worse, Brian and Zee’s respective partners are giggly and believably effusive but never more than just arm candy for rambunctious men whose growing interest in testing themselves inevitably bites them in the ass in a big way.
What Ayer does thankfully at least convey is a sense of dread that his chintzy and largely unnecessary use of first-person POV camerawork only heightens. The discovery of human bodies in a cartel is handled with as much head-spinning expediency as the sudden appearance of special agents, whose long-running investigation Brian and Zee inadvertently interrupt when they pursue one of Brian’s characteristically sound hunches. Bodies come and big-shots go without introduction, making Ayer's film an impressionistic blur of implied violence.