Directed by Alison Klayman. 91 mins. In cinemas now.

Over the past few weeks, unused footage from Alison Klayman’s documentary The Brink has made headlines in the UK. For two years, Tory leadership contender Boris Johnson has repeatedly denied ever consulting with far-right media executive and strategist Steve Bannon – the fear-mongering mogul who guided Trump to power under the philosophy that “Hate is a great motivator”. But this month, Klayman released footage where Bannon confirms that he and Johnson spoke on the phone, texted a lot, and got to know each other “quite well” following Trump’s election.

Why Bannon’s influence over political leaders is a cause for concern is highlighted in Klayman’s film, a classic cinéma vérité documentary that follows Bannon for 18 months after his very public ousting from the White House. Klayman gains remarkable access to Bannon and his team, as the strategist embarks on a new international initiative to bring “economic nationalism” – aka racism – to populist political organisations in Europe.

Klayman (Ai Weiwei: Never Say Never, Take Your Pills) is a quiet though not invisible observer, and captures the most disconcerting aspect of Bannon’s influence: the sheer banality (of what, you can decide yourself). Bannon, who like Johnson has cultivated a rumpled, unthreatening aesthetic, is an easy communicator. He calls people “dude”; he de-escalates hostile interactions with humour; and his daily routine consists of a lot of dull meetings in nondescript hotel rooms. But it’s the aim and the impact of these meetings, his cosiness with white supremacists, and the devious duplicity behind the persona, that are alarming.

Klayman’s intimate footage captures this: his temper; his pathological lying; his repeated use of the dog-whistle racism and anti-Semitism echoed by terrorists and extremists. One brilliant scene sees Guardian reporter Paul Lewis calmly but firmly confront Bannon over his coded language and outright lies; for once, we see Bannon’s affable front waver, and his charade continues to disintegrate.

However – this will all be clear to Bannon’s critics. Klayman’s passivity leaves enough room for his fans to view the same footage and admire his wheeling and dealing. And for a man who openly declares that “the most important thing Trump taught me is that there is no bad media”, one wonders if this is enough.