“I’m a walking cliche, what can I tell you?”

So says Kat, world-weary ex-cop, as she’s castigated for munching her Coco Pops with vodka instead of milk soon after we meet her. She’s not wrong. Off the force but still on the case, determined to solve the abduction of a child, she’s doing it all for her young daughter who she loves so much she’s even kept all of her milk teeth.

Needless to say it’s odd to see Sophie Okonedo (Hotel Rwanda and so much more) playing those well-worn tropes, she’s an Oscar nominee and hardly needs to accept material so beneath her. But of course, as usual in the series, nothing is quite what it seems, although I won’t be taking you any further into the plot.

I did initially think we were heading into a partial retread of The 12 Days of Christine from series 2 until it was made clear(ish) what was happening. This is certainly an episode that will benefit from a rewatch; some of the clues I picked up on in retrospect but there’s sure to be others that passed me by.

Okonedo, as magnetic on screen as always, is joined by Robin Weaver (The Muppet Christmas Carol/The Inbetweeners) and Siobhan Redmond (Bulman/The High Life), as well as, of course, Steve Pemberton and Reece Shearsmith.

Verdict: A clever tale with an excellent cast, which takes a couple of well-worn tropes and gives them an extra little twist. My favourite of the season so far. 8/10

Andy Smith