Jed Mercurio knows a thing or two about what television viewers in Britain like. His series “Bodyguard” was the highest rated show there (outside of the World Cup) in 2018. And now the fifth season of his “Line of Duty” is the highest rated British drama of 2019 so far.
In the case of “Line of Duty,” whose newest six-episode season comes to Acorn TV on Monday (joining the previous four), millions of viewers apparently like a cocktail of four parts forensics to one part action, with a twist of sensationalism and a splash of melodrama. It’s not good for you, but it will definitely give you a buzz.
In Season 5, the focus remains on three detectives in an anti-corruption unit (the British equivalent of internal affairs) in a grimy, unnamed city that resembles Birmingham. (The resemblance was strongest in Season 1, when the show was filmed there; subsequent seasons have been shot in Belfast, in Northern Ireland.)
Steve Arnott (Martin Compston) is walking again after being thrown down a flight of stairs in Season 4, and more than a little resentful that his partner, Kate Fleming (Vicky McClure), got the promotion to inspector that was supposed to be his. (Given the show’s minimalist approach to humor, it’s very funny when he has to call her “Ma’am.”) Ted Hastings (Adrian Dunbar) — their gaffer, or boss — is in a general state of decline, living in a hotel and dealing with a level of debt that’s particularly unhealthy for someone whose job is to ferret out cops on the take.
These three tackle a new case, and a new dirty cop, each season, but a distinguishing feature of “Line of Duty” is that all the cases run together in a single, continuing story. Someone in the top ranks of the police is in cahoots with organized crime, but he or she is always just out of reach, pulling the strings of the people Steve, Kate and Ted bring down. In the sort of cloak-and-dagger detail Mercurio favors, the mastermind is known only as H, a bit like the unseen Number One in “The Prisoner.”
With a sixth season ordered by the BBC, it’s not really a spoiler to say that the search will continue. In the meantime, this season’s antagonist is a rogue undercover cop — to say who plays him or her would be a giveaway — who acts as a kind of doppelgänger for our heroes, employing the tactics that they might wish to.
A primary strength of the series, beyond Mercurio’s ability to precisely blend his cop-show formulas, has been its gallery of charismatic, conflicted “bent” cops, played by an exceptionally able roster of actors: Lennie Harris, Keeley Hawes, Thandie Newton. If the new season falls slightly short of the show’s usual standard, it’s because neither this character nor the performance in the role is as interesting as its predecessors.
Otherwise, all the elements are in place. The show still centers on its signature interrogations, the equivalent of an action show’s fight scenes — long and static but intricately choreographed, fought through precise exchanges of haikulike jargon. (Regular viewers understand U.C.O., O.C.G. and D.I.R., and know that an officer can insist on being questioned by someone of superior rank.)
And once or twice an episode, the satisfyingly nerdy police-procedural grind will be punctuated by breakneck rushing about (“We’ll have to blue-light it!”) followed by some improbably violent or lurid action. That these situations are generally less baroque than in past seasons — fairly straightforward hijackings and shootouts, with no one being thrown from a hospital window or waking up to an amputated hand — will be either an improvement or disappointment depending on your taste.
“Line of Duty” works through a careful balancing act — Mercurio can overplay the tension, and get away with a high degree of ambient implausibility (how many times can Kate go undercover in one medium-sized city?), as long as he underplays the longer sequences of investigation and the dips into the cops’ private lives. It’s similar to Dick Wolf’s “Law & Order” formula, and it makes “Line of Duty” a better show than the more highly rated “Bodyguard,” where Mercurio leaned heavily into melodrama.
The key underplayer is Compston as the combative Steve, the show’s moral center between the more pragmatic Kate and the more blustery, self-righteous Ted. Responding to station-house shootouts and sinister conspiracies with a raised eyebrow and a tight frown, he’s the beacon of sanity who allows us to enjoy the craziness guilt-free.
This article originally appeared in The New York Times.