Happily, there’s hope for Spiral junkies – as series six ends, we bring you news that series seven has just gone into production. This is just as well, because these last dozen episodes have been an object lesson in how to make TV drama for the mind and body, nimbly evading cop show genre-pitfalls to bring us carefully-shaded characters operating within a Venn diagram of overlapping grey areas. Big kudos, yet again, to showrunner Anne Landois.

The “insider’s guide to the music business” tag attached to Hits, Hype and Hustle: An Insider's Guide to the Music Business (BBC Four) dangles the carrot of all kinds of clandestine scams being exposed, such as extortionate recording contracts, systematic chart-rigging or Mafia rackets involving cut-out records. Instead, this episode was merely a meander through the history of live performances in rock music.

We’ve seen some “interesting” series filling BBC Four’s celebrated Saturday evening slot recently, which if nothing else have prompted plenty of below-the-line discussion. Happily, we can now turn our backs on all that and hail the return of the ace Paris-based French cop show Spiral.

To misquote Marx (Karl, not Groucho), comedy repeats itself, the first time as farce, the second time as a tragedy. The early days of broadcasting bred comedians whose work lives on in the nation’s marrow. But being Frankie Howerd or Kenneth Williams or the Steptoe actors was no laughing matter.

It’s remarkable how pervasive the Scandi-noir formula has become, with its penchant for weird and perverted killers, labyrinthine plotting and intriguingly flawed protagonists.

Long before Barack Obama spoke about the audacity of hope, the Voyager mission left the Earth driven by something else: the audacity of curiosity. What do the outer planets look like? What are they comprised of? And what’s beyond that?

A thankless task, perhaps, to find oneself following in the footsteps of the berserk Spanish melodrama I Know Who You Are (theartsdesk passim). However, BBC Four’s new Saturday night import, whose first series was shown on Channel 4 a couple of years ago, is a French cop show which knows what it’s talking about and does the simple stuff right.

So, if you’re reading this you probably trudged all the weary way to the very end of I Know Who You Are. Or you didn’t but still want to find out what the hell happened. After 20-plus hours of twisting, turning, overblown drama, long-service medals are in order for all who flopped over the line. We are probably all feeling as drained and battered as half the cast: black-and-blue Santi Mur, anaemic Ana, slapped-up Pol, smashed-to-smithereens Heredia.

As Motherland settles down into its first series proper after last year’s pilot, it still seems to be going at a fair gallop.

“There is something odd, I suppose, about anyone who betrays their country.” It’s an excellent opening line, particularly when delivered in director George Carey’s nicely querulous narrative voice, for Toffs, Queers and Traitors (BBC Four).