André Leon Talley is a standout figure in fashion: a 6ft 6in African American dressed in kaftans and jewellery so big you can probably see it glittering from space. For years he worked as Anna Wintour’s right-hand man at American Vogue, but really what made him famous was the bling.

From a distance he appears faintly ridiculous, like a character from Zoolander. But with her thoughtful, unexpectedly serious film Kate Novak proves Talley’s doc-worthiness. He emerges here as a man of tremendous resilience whose outsider success paved the way for people of colour in the elitist world of fashion.

Talley, now 68, grew up in the segregated south raised by his grandmother. As a teenager he was stoned by white students on the local university campus where he went to buy Vogue. In the 70s, he was the only black man on the front row in Paris. Superstar designer Tom Ford calls him the “last of the great editors”. (You can measure Talley’s influence by the heavyweight fashion folk gushing on camera, some more gruesome than others.)

In the past Talley rarely spoke about racism. He opens up a little here, describing a fashion PR in Paris who gave him the vile nickname “Queen Kong”. In a moving scene he cries looking at Vogue’s 2009 cover featuring Michelle Obama: “I wish my grandmother had been alive to see this.”

Talley strikes you as a man of sincerity and depth behind all the air-kissing and lamé. He liveblogs Donald Trump’s inauguration for the New York Times with a roomful of political journalists – they’re all smirking with detached ironic amusement, the very definition of liberal elite. Talley looks as if his world has fallen apart.

There’s plenty of Zoolandery silliness, too. Best of all is the peevish phone call Talley makes from a spa, after a diet slip-up, to his assistant, with a reminder to find out how many calories are in a biscuit: “It was a big puffy biscuit!”