Any show that starts with a shot of a naked bubble-butt is likely to grab the attention – especially when it belongs to Milo Ventimiglia – but, alas, the barefaced cheek of this opening gambit becomes all too symbolic. This Is Us scrapes the bottom of the barrel of American TV drama. However, its saving grace could be that it does so with irony – there are 17 more episodes to come.

Anyone hoping for a few laughs and a nice bit of catharsis after enduring the eight unstintingly miserable episodes of The Missing would have got none of the former and hardly any of the latter. Writers Jack and Harry Williams had sprung most of their biggest surprises in earlier episodes, such as the revelation that the real Alice Webster was still alive and being held captive in Adam Gettrick's Swiss Alpine cottage, and indeed that Gettrick was the abductor of the girls around whom the story has revolved.

Howard Brenton (Christie in Love) and Ruth Rendell (Thirteen Steps Down) are just two of the many writers inspired by the sordid goings-on in 1940s Notting Hill. John Reginald Christie was a postman, a policeman and a psychopath who, as a back-street abortionist, enjoyed killing for company. A fantasist with an iron grip, he ensured that his lodger, Tim Evans, was the first to be hanged for his crimes.

TV can be a powerful tool of redemption. Take Strictly Come Dancing – anything that can shift perception of Ann Widdecombe from poisonous homophobe to innocuous have-a-go hero is dark, dark magic indeed. Just this week, the Strictly dancefloor has finally bid goodbye to Ed Balls after housing him for almost as long as the role of Shadow Home Secretary, and society is opening its arms to him – a politician with a reputation as a ruthless bully. It's another example of TV-led Munchausen syndrome by proxy.

The Kenwood Chef! Intercity 125! Kodak Instamatic! Wilkinson Sword disposable razors! Bus shelters! Parking meters! They were all designed by a British genius, Sir Kenneth Grange, who appeared here as the subject of a short and disarmingly confident interview, intiating a series of such interviews. The programme marked the opening weekend of the £83m transformation of the Grade2* redundant Commonwealth Institute in Kensington into the new Design Museum, which showcases both British and international contemporary design.

The sketch format goes in and out of favour. It was huge in the 1970s, crawled under a rock when alternative comedians found other means of expression, and was reinvigorated 20 years ago by genuinely inventive shows like Big Train and The Fast Show. Since then, easily the biggest kid on the block has been Little Britain, which married mainstream appeal with a flair for subversion.

This is a documentary about a minority in a minority, a riff on young, gifted and black. And how better to attract both practitioners and audiences to classical music than by encouraging diversity? The totally startling statistic was that in the UK, only five per cent of classical musicians are black or from ethnic minorities.

The Jeremy Clarkson trio must have been vastly amused by the disastrous progress of the Chris Evans version of Top Gear, which staggered across our screens in the summer and prompted the new host to fall on his sword, but they shouldn't be resting on their laurels just yet. This long-awaited debut of their new show, The Grand Tour, was big, brash and lavishly budgeted – Amazon have reportedly stumped up £4.5m per show – but it flirted dangerously with bloat and bombast.

For those new to this Irish crime series, a brief catch-up. Jack Taylor (played by Iain Glen at his world-weary best) is a hard-drinking maverick loner ex-cop who left the Garda Siochána (Ireland's police force) after hitting a politician to investigate cases as private detective. He says there aren't many of his kind in Ireland, as the job is “too close to being an informant – a dodgy concept”.

“Why is everyone from your school a criminal crackhead?” “Why is everyone from yours a Tory minister?” These questions lie at the heart of Zadie Smith’s NW. Keisha (the wonderful Nikki Amuka-Bird), aka Natalie, is married to wealthy Frank (Jake Fairbrother), who’s asking the crackhead question. Leah (Phoebe Fox), who answers back, is her best friend – though that’s no longer a given.