Dominic Cummings (Benedict Cumberbach).

By Calum Henderson

Lowdown: Brexit: The Uncivil War
(Sky's wording:) Available now on Sky Go and Sky On Demand, or catch it on BBC UKTV on Monday 1 April, 9.30pm

The last time I saw Benedict Cumberbatch he was on about 17 different drugs, stumbling around New York City with a death wish. This was in Patrick Melrose, not real life – you hope he takes better care of himself than that, though he does seem to be getting increasingly method with every role, so who knows. This time he's back in London, going bald and masterminding the Leave campaign in the BBC's Brexit: The Uncivil War.

Cumberbatch is Dominic Cummings, the campaign director for Vote Leave, the political Billy Beane who threw all convention out the window and went full Moneyball on Brexit by relying on algorithms and statistics. "Everyone knows who won," he says in the introductory monologue – rambling, frantic, classic Cumberbatch – "but not everyone knows how." In the 90 minutes that follow we find out in a way that's roughly a thousand times more entertaining than you ever thought something about Brexit could possibly be.

The whole thing basically plays out like a political heist movie. The main point of difference as far as I can tell is that most heist movies have at least one character who's, you know, cool. Every character in Brexit is either a sickly-looking nerd and/or a complete and utter plonker. The closest you get to cool, in the Guy Ritchie movie sense of the word, is UKIP donor Arron Banks, who comes across a bit like Robbie Williams if Williams was part of the Only Fools and Horses Cinematic Universe.

Banks is just one small part of the 1000-piece Leave jigsaw we watch falling into place in the first act. There's smarmy UKIP MP Douglas Carswell, who looks a bit like Phil from Kirstie and Phil (Location, Location, Location). We first see him having a clandestine meeting in the National Gallery with skittish lobbyist Matthew Elliott, who accurately points out their rendezvous point is "very Tinker, Tailor…"

Elliott's the one who suggests Cummings, a political outsider astutely summed up to the Remain team by the Government communications director as "basically mental". He wants to "hack the political system" and gets straight to work by scrawling on the office walls like Good Will Hunting (more like Bad Will Hunting) in search of a campaign message. Eventually he settles on "TAKE CONTROL", which everybody seems to like.

Like Vice, the biographical comedy-drama about the rise of former US Vice-President Dick Cheney, Brexit's subject matter and recency have inevitably made it polarising. Some have criticised the way it portrays figures like Nigel Farage and Boris Johnson as comedy buffoons, like the uncle out of Harry Potter, when the reality is a bit more serious. That's probably fair enough.

Admittedly I can only speak as a total Brexit dunce when I say I thought Brexit: The Uncivil War was brilliant – smartly written, clearly plotted, with Cumberbatch doing his usual Cumberbatch things. While the debate has moved on a bit since the referendum, it's helpful – at least now I have some frame of reference for my all Scottish uncle's apoplectic Facebook posts.