Season three of Luther finds the perpetually harried Detective Chief Inspector John Luther (Idris Elba) in straits that might be direr than ever, which is saying quite a bit for a man who grappled with his ex-wife's murder by an old friend and, more recently, blackmail at the hands of vicious underage sex traffickers, all while battling the deranged serial killers who materialize seemingly every other day on the beat. Now, Luther must symbolically atone for his own tendencies to take the law into his own hands, as he's thrust into the path of several revenge killers as well as overzealous, quasi-corrupt Detective Superintendent George Stark (David O'hara), who's joined in his obsessive pursuit of the titular inspector by Erin Gray (Nikki Amuka-Bird), that reliably unimaginative stick-in-the-ass copper whose career Luther managed to nearly destroy last season.
Luther embodies almost everything that's refreshing about the traditional British crime drama. The matter-of-fact resistance to outward emotional flailing in the best British crime novels and television shows contrasts favorably against those works' often sweatier and more hyperbolic American cousins, and this cool tendency allows one to swallow a larger amount of violent, symbolic, melodramatic malarkey. Luther's plot specifics are rarely unusual for the genre, and few of them are believable, particularly Luther's blossoming romance with master serial killer Alice Morgan (the stylish and scene-stealing Ruth Wilson), but creator and writer Neil Cross understands that the genre traditionally lends itself to examinations of class systems. We're afforded a generous snapshot of Britain's racial mixing pot (there are several interracial romances, all presented without the slightest hint of self-consciousness), and the series is explicitly aware of the challenges a post-Thatcher regime has faced in its efforts to manage the vast portions of the populace who correctly feel as if they've been swept under a rug.
The killers that Luther routinely faces are often mad, but most of them are also working-class people with chillingly relatable grudges against a bureaucratic labyrinth they've come to see as fit only for shuffling papers—and many of the cops pursuing these killers would be disinclined to argue that perception with them. Early in the season, Luther is forced to investigate the death of an obese shut-in who's revealed to have been tormenting a disabled girl online, which inadvertently led to her death. (Spoilers herein.) The DCI and his frequent partner, Justin Ripley (Warren Brown, vivid and likeable in a tricky role), quickly manage to find the shut-in's killer: the girl's father, who's still so heartbroken he can barely make the cops tea without crumbling into tears on the kitchen floor. Contemptuous of the shut-in's vindictiveness, Luther eventually manages to carelessly place a phone call that warns the father of his approaching capture by the police.
That sort of policing manages to get Luther in trouble, though admittedly in fashions that don't ultimately matter. Like most crime fiction with a pointedly liberal point of view, Luther is torn between promoting democratic ideals and indulging the bloodlust that makes for good lurid entertainment with vicarious closure. Season three echoes back to the beginning of the first season, where Luther damned himself by allowing a pedophile to drop to his near-death. The new episodes comprise a variety of clever riddles, ironies, and resonances devoted to the challenge inherent in remaining impartial in the face of waging hopeless warfare that never appears to help the right people. Luther's greatest foe is a serial killer who offs the kind of people whom he has himself killed, but the killer almost immediately devolves into a self-righteous maniac who spouts gibberish that parodies the swagger of Luther's own vendettas.
Season three is consistently toned, crisp, mean, and morally irresolvable, which is just right for a series that's examining the pent-up demons of the men and women who attempt to affirm an illusory sense of stability in the midst of a decaying wasteland inhabited by lost people. The season ends on several notes of potential finality for the series as a whole, the last of which is a superficially happy ending that, upon further reading, scans as a perverse black joke. Luther embraces the love of his life: the one woman willing to enable his deepest desires to do whatever he pleases however he pleases. With this woman he has the power to throw the establishment he serves away in favor of what might eventually become a crime spree. Luther, tiring of moral ambiguity, fed up with compromise and disappointment, finally exhales a tragically earned implicative sigh of "fuck it."