The week in TV: Ludwig; Celebrity SAS: Who Dares Wins; Apples Never Fall; Surviving October 7; Small Town, Big Riot – review

(BBC One) Celebrity SAS: Who Dares Wins (Channel 4) Apples Never Fall (BBC One) Surviving October 7: We Will Dance Again (BBC Two) Small Town, Big Riot (BBC Three)

Comedy thrillers are a tricky genre, too often imploding into a tonally bumpy mess: usually not quite funny enough, and about as gripping as a game of half-hearted yuletide Cluedo.

Enter BBC One with Mark Brotherwood's six-parter , set in Cambridge and the latest attempt at cosy crime (modern division). David Mitchell stars as the titular Ludwig, "the Elvis Presley of puzzle-setters": emotionally repressed, out of sync with modern times, living in Cambridge and practically mummified in a sensible corduroy jacket. Yes, Ludwig does give us aged-up Mark Corrigan from Peep Show. From some angles, with the beard, even a depressed David Blunkett.

When his sister-in-law, Lucy (Anna Maxwell Martin), reveals that her husband, his police detective twin brother, is missing, Ludwig takes on his identity to find out what happened, and gets roped into solving crimes. As a premise it's fairly absurd, as is the fact that Ludwig employs his puzzle skills to solve a (very basic) mystery each episode, which seems mainly an excuse to give actors such as Derek Jacobi and Felicity Kendall cheeky guest spots.

However, the more episodes I watched, the more I liked it. There's a cracking cast, including Maxwell Martin, Sophie Willan from Alma's Not Normal , and Dipo Ola as an unwitting detective. Towards the end, the overarching mystery (what happened to Ludwig's twin?) slams into place. There are genuinely funny moments ("Do you follow the football?" asks Ludwig, trying to bond with police colleagues). The series also seems intent on trolling the Oxford-centric Inspector Morse (substituting halcyon scenes of Cambridge).

Ludwig rather overplays the master-puzzler theme (it's like trying to whip up excitement over someone filling in a sudoku grid), but, in its best cosy moments, it's the closest any British production has got to the ratings juggernaut of US hit Only Murders in the Building .

It's interesting to see reality television go cold on politicians. There aren't any in the current Strictly Come Dancing lineup and while I'm a Celebrity... Get Me Out of Here! featured disgraced former health secretary Matt Hancock and then Nigel Farage (now MP for Clacton), it's reported to be giving Westminster a miss for the next series.

Now Channel 4's special forces training show Celebrity SAS: Who Dares Wins? (which also featured Hancock) returns with no politicians, though there is journalist Rachel Johnson (sister of Boris). To her credit, she doesn't pretend she's included for any other reason, as she stamps through New Zealand mud, navigates high drops, and is dragged before SAS instructors for an "interrogation".

Johnson talks of people calling her family the c-word in Sainsbury's and how she's been a "punchbag... who's had to soak up a lot of the anger people have felt because of the huge decisions that have been taken by my brother for the country". It beats the likes of Farage giving it primetime populist jazz hands, but I'm not sure reality TV is completely over its politics addiction.

Apples Never Fall is the latest thriller to be adapted from a Liane Moriarty bestseller (Big Little Lies; Nine Perfect Strangers), and on paper it sounds juicy. Annette Bening and Sam Neill star as Joy and Stan, now unhappily retired from their Floridan tennis academy, surrounded by their spoiled adult brood, played by among others Jake Lacy and Alison Brie, and a sinister stranger (Georgia Flood) who's infiltrated the family. In the first of seven episodes, Joy goes missing and suspicion falls on volatile and obnoxious Stan.

It all feels dated and stodgy (more claggy crumble than tangy apple) and there are so many Joy-heavy flashbacks you keep forgetting she's missing. I'm sticking with it on the grounds that anything involving Bening and Neill is watchable, but the TV-thriller racket strings are starting to look frayed.

The week's most devastating documentary was Yariv Mozer's 90-minute Surviving October 7: We Will Dance Again, shown on BBC One. It's a gruelling, in-depth retelling of the massacre at the Nova music festival in Israel (among the sites attacked by Hamas on 7 October last year) at which 364 people were murdered, with others injured or taken as hostages.

The events are related by survivors in interviews, in quasi-real-time, using footage from mobile phones, CCTV, and Hamas's own body cameras (they arrive on motorbikes waving AK-47s). The documentary starts with the trance festival (at sunrise, when rockets start falling, many people are "rolling" on ecstasy or LSD), then erupts into a bloodbath. At the festival (people huddling under stages or hiding in fridges), on roads (littered with corpses and burnt-out cars), and in farmland (bullets whizzing past as they run).

The film doesn't cover the wider conflict. Aerial maps show the shocking proximity of Gaza, there are brief scenes at places such as the Be'eri kibbutz , but the main focus is the Nova festival-goers. Images of high-profile victims such as Shani Louk and Hersh Goldberg-Polin appear as if in a terrible dream. Survivors are still traumatised, as they try to honour the dead. "I accepted death," says one young man almost blankly. Be warned: this is a powerful, but highly graphic, harrowing watch. I can't stop thinking about it.

On BBC Three, the two-part docuseries Small Town, Big Riot looks into the 2023 disorder in Kirkby, Merseyside , outside a hotel housing asylum-seekers, which led to arrests and convictions. Bafta-winning documentarian Mobeen Azhar states his aim: "I want to know why a protest in a little town turned into a full-scale riot."

His investigation takes him beyond Kirkby to online misinformation and far-right groups stoking unrest. The series was mainly made before this summer's riots (starting in Southport after the stabbing of three children and spreading across the UK), which Azhar refers to briefly at the end.

What emerges is an intriguing study of supposedly spontaneous protests and disturbances. What Azhar brings to his subjects (his documentaries include A Black and White Killing: The Case That Shook America ) is an indefatigable commitment to the deep dive. Old-school investigative journalism that just won't quit.

Star ratings (out of five) Ludwig Celebrity SAS: Who Dares Wins Apples Never Fall Surviving October 7: We Will Dance Again Small Town, Big Riot

What else I'm watching The Great British Bake Off (Channel 4)

The return of the pastel-hued baking contest of triumphs and disasters, and a reminder that it's not over until the buttercream curdles. Judges Paul Hollywood and Prue Leith are joined by presenters Noel Fielding and Alison Hammond.

Monsters: The Lyle and Erik Menendez Story (Netflix)

Ryan Murphy's true-crime drama about the US 1990s case of two brothers killing their parents – then saying they'd been abused. Overblown, overlong and overacted, but strangely compelling.

Mortimer and Whitehouse: Gone Fishing (BBC Two)

A new series of gently rebellious riverbank musings from Bob Mortimer and Paul Whitehouse about fishing, life, ageing, death, and naturally a quick nip to the pub.