TV preview, Theresa v Boris: How May Became PM (BBC2, Sunday 9pm): fast-moving events get the lookalike treatment

Plus: Brexit Means Brexit (BBC2, Wednesday 9pm); Who Should We Let In? Ian Hislop on the First Great Immigration Row (BBC2, Thursday 9pm); Riviera (Sky Atlantic, Thursday 9pm); Pitch Battle (BBC1, Saturday 7.30pm); Merciless (C4, Sunday 10.15pm)

Jacqueline King plays the Prime Minister in this inevitably timely drama-documentary (BBC/Juniper Communications/Katherine Edwards)

When the BBC commissioned a drama-documentary about the political aftermath of last June’s EU referendum, Theresa v Boris: How May Became PM, it was probably feeling rather relaxed about when to actually schedule it.

That must have changed when May stepped out of No 10 and called a snap election, but even then, like the rest of us (and May herself, it seems), they wouldn’t have been unduly worried that it was about to suddenly become in danger of being badly dated.

Well, wham! It’s now being rushed on to our screens, and given the backroom coalition-building and knife-sharpening currently happening in Westminster, it couldn’t be more timely. Eye-opening even. As I write, Boris Johnson is probably holding his legendary get-to-know curry nights, although there are now only 318 Conservative MPs to cook for instead of the 331, and presumably Michael Gove’s invite will be lost in the post.

The drama bit involves various approximate lookalikes, the actor Will Barton as Boris with what appears to be a mop from the props cupboard plonked on his head, while the most entertaining scene involves the visit of Team Gove, spreadsheets in hand, to Boris’s home – their host inviting them to kick back and use the swimming pool. This obviously was never going to be a meeting of minds.

Meanwhile a sprinkling of talking heads, MPs willing to appear as themselves, gee the story along, while Gavin Williamson, PPS to David Cameron turned Theresa May’s Chief Whip, and a man unknown to most of us, steps out of the shadows as the most compelling figure, a cross between Peter Mandleson and The Thick of It’s Malcolm Tucker.

Will Barton plays Boris Johnson in ‘Theresa v Boris: How May Became PM’ (BBC/Juniper Communications/Katherine Edwards) (BBC/Juniper Communications Limited - Photographer: Katherine Edwards)

The real Boris Johnson appears in Brexit Means Brexit, a documentary filmed by Patrick Forbes, the award-winning director who made last year’s Brexit: a Very British Coup?, and which follows events in the 12 months following the referendum vote. With the story still unwinding daily, Forbes’s film was obviously unavailable for preview, but promises to reveal the “low politics, high ambition and bitter personal animosities” involved, as Gina Miller attempts to challenge Brexit in the courts, and Nigel Farage heads off to Trump Towers to snap selfies with the newly elected President.

Just when you hoped that Katie Hopkins might go and join them – or had metaphorically been entombed in concrete and buried down a disused mineshaft – up she pops in Ian Hislop’s latest history lesson, Who Should We Let In?, a survey of 200 years of British immigration policy. Or the lack of. The Victorians practised an Angela Merkel-style open-door policy and prided themselves on being “the asylum of nations”, and it wasn’t until the First World War that restrictions were introduced. Hopkins’s contribution isn’t worthy of repetition, but is par for her course.

There’s a different class of immigrant on the French Riviera. From its opening credits onwards, Riviera obviously styles itself on The Night Manager, but with no Tom Hollander to provide light relief here, it’s just a rather vacuous, glossy thriller about boring rich people. The surprise is that the Booker-winning author John Banville had a hand in writing it.

Pitch Battle is yet another talent contest for Saturday nights, this one involving choirs of all stripes, and hosted by Mel Giedroyc, who is going to be everywhere on a grateful BBC in coming months after she declined to follow The Great British Bake Off to Channel 4.

And, finally, Merciless (or “Ojos Sin”, as it’s called in its native Brazil) is the latest Walter Presents subtitled drama to be sampled on Channel 4 before disappearing on to All4. Luana Piovani plays a criminal profiler so glamorous it’s a wonder that her colleagues can concentrate on the job in hand – the serial murders of pretty young women. I’m afraid so, and there’s nothing subtle about the head-banging Merciless, which is being presented as “a Brazilian Dexter”. It’s what’s known in the trade as an elevator pitch.