Dir: Steve McQueen; Starring: Shaun Parkes, Letitia Wright, Malachi Kirby, Rochenda Sandall, Gershwin Eustache Jnr, Gary Beadle, Jack Lowden, Alex Jennings, Sam Spruell. Cert tbc, 126 min.

“Great men make history,” the Trinidadian historian CLR James once wrote, “but only such history as it is possible for them to make.” At the start of Mangrove, the fantastically gripping and galvanising new film from Steve McQueen, Frank Crichlow (Shaun Parkes) would settle simply for making a living. A first-generation member of London’s West Indian community, Frank is the owner of the Mangrove, a modest restaurant specialising in Caribbean cuisine and something of an impromptu neighbourhood hub.

The place is Notting Hill, though the year is 1968, which means Hugh Grant is nowhere to be seen, and the locals’ doors are less likely to be knocked on by a paparazzi-shy Julia Roberts than a policeman nursing a truncheon and a grudge. Mangrove is the opening gala at the socially distanced and streamable 2020 London Film Festival, which launches this evening (October 7) with a muted premiere at the BFI Southbank. It’s also the first entry in McQueen’s landmark Small Axe project: a collection of five films about 20th-century black British life that will be broadcast next month on BBC One.

Like most of the Small Axe films, Mangrove’s story is a true one, and Frank is its hero – albeit an initially reluctant one. All he wants is to be able to run his restaurant in peace – but this proves impossible when it is repeatedly and violently raided at the instigation of the openly racist PC Pulley (Sam Spruell), even though there are no illegal goings-on to be uncovered. Finding common cause with two young activists, Altheia Jones-Lecointe (Letitia Wright) and Darcus Howe (Malachi Kirby), Frank joins a protest march on the local police station and is arrested and charged with incitement to riot alongside Altheia, Darcus and six others who would become collectively known as the Mangrove Nine.

Their subsequent trial at the Old Bailey feels at first like a stitch-up in the making, yet it slowly and rivetingly transforms into a pivotal moment in the story of UK race relations. Just as they did in real life, both Altheia and Darcus choose to represent themselves – which means that in the most famous court in the land, the black corner is being fought by black voices. McQueen and his co-writer Alastair Siddons carve their tale cleanly in two: an hour-long vivid, enveloping period piece followed by an hour of heart-prickling legal theatre, without a wasted second between the two.