At last, after three series, Line of Duty delivered a denouement that felt like a satisfying jackhammer to the solar plexus. In the first series the bent copper under investigation escaped justice by jumping in front of a lorry. In the second there were more loose ends than are generally produced by a rope factory. It turns out that patience is a virtue and we should all have had faith.

I interviewed Merle Haggard once and he’s a slippery old snake: dry, reserved and fiercely intelligent, with an ornery pride and an oft-used gift for riling people. I’m not sure we got to know him all that much better after Gandulf Hennig’s superb documentary Learning to Live with Myself, but it was a hell of a ride none the less. A man with hidden depths buried inside his hidden depths, Haggard said towards the end of the film that he had struggled his whole life to achieve his aim of being “self-contained, totally”. He wasn't about to go all therapy-speak on our asses now.

Can't get enough Scandi Noir? Then why not make your own? With the aid of Hans Rosenfeldt, creator of The Bridge and installed here as screenwriter, ITV has.

If you were expecting Rowan Atkinson to say "bibble" or make those Mr Bean gurgling noises, you came to the wrong classic detective drama. To play George Simenon's timeless French detective in a story subtitled "Maigret Sets a Trap", a melancholy, interiorised Atkinson spent most of his time sitting and thinking. Despite the mumsy ministrations of Mme Maigret (alias Lucy Cohu), he relied mostly on his pipe for company as he struggled to unmask a serial killer of women in Montmartre.

Halfway through its 10-week run, The People v OJ Simpson: American Crime Story appears to be running in real time as it slowly, painstakingly tells the story of how one of the US's biggest sports stars was accused of the murders of his ex-wife Nicole Brown and her friend Ronald Goldman in 1994. But moving at what is – by modern television drama standards, at least – a glacial pace allows the creators to burrow deep into the American psyche and, more pertinently, examine the deep-rooted racism lurking in parts of US society.

Murder is entertainment, which is why crime and the legal process are on television every night. But where drama and documentary focus on criminals and the police who catch them – and the barristers who cross-examine them in court – vanishingly little attention is paid to the worker bees of the legal process. That's partly because the Crown Prosecution Service is a shy organisation. The Prosecutors: Real Crime and Punishment is the first time cameras have been allowed to watch the CPS at work.

Three and a half years ago the writer Robert Jones and producer Kath Mattock came at the crime genre from an unusual angle. Instead of having characters in a murder case talk to one another, they all addressed the camera directly, each offering their own apparently unmediated viewpoint. The title took its cue from the direct style: Murder. Murder: Joint Enterprise won a Bafta. It has taken a while, but the single experimental film has given birth to a short series of three new cases.

Exposed is a film suffering from blunt force trauma to the head. Director Gee Malik Linton’s name only remains as screenwriter after his largely Spanish-language film – more meaningfully called Daughter of God and centring on Dominican-New Yorkers – had a helpful supporting role from producer Keanu Reeves greatly expanded by its US distributor, hoping to transform it into a Keanu cop movie.

“It’s routine, it’s procedure.” “It’s wank, it’s toss.” As you can tell, Happy Valley is back. If Sally Wainwright made bespoke ironmongery or dry stone walls or exceedingly good cakes, her work would come by royal appointment. Instead you can tell she’s good because she accumulates awards, including most recently a couple of BAFTAs for series one, and attracts actors from the farthest-flung corners of northern drama such as Cucumber and Downton’s downstairs, all gagging to speak her pearly dialogue.

We have been here before – literally. Morse and his colleagues discreetly observe a gangster’s funeral in Kensal Green cemetery – just as they did in Promised Land, one of the best episodes of Inspector Morse, first broadcast in March 1991. A quarter of a century has passed (along with John Thaw) yet ITV are still trying to breath new life into the ratings warhorse.