“Film is about to start”. Those playful words introduce Martin Scorsese’s portrait of his mum and dad, Catherine and Charlie, a frantic-eyed, finger-chewing, pair of Sicilian-born New Yorkers who despite (or perhaps because of) their nervous energy, are a riot. This movie should really be called Parents: They Buck You Up. The documentary, released in 1974, breaks ground without seeming to try.

Marty is the one ostensibly in charge, but Catherine and Charlie, who we first meet in the sitting room of their tiny apartment, never feel like his subjects. That’s partly because they keep asking questions. Five minutes into the film, 62-year-old Catherine (all big glasses and white candy-floss hair) leaps to her feet. As she leaves the room, she calls out: “How am I doing so far?”