This is an affectionate tribute to John Grierson, who founded and led the British documentary film movement in the Thirties, and who later established in Montreal, what grew into the largest documentary film studios in the world, the National Film Board of Canada.

His story is told through reminiscences of his major collaborators, and collected interview material with Grierson himself. Photographs, newsreels, and excerpts from Grierson's films (Drifters, Nightmail) help to bring into focus the fiery personality of this visionary and committed film maker.