Robert Altman was showered with awards in his lifetime, but no accolade is as overbaked as his bestowal of the title of VIP: Very Important Pothead. The mind behind films like Popeye (1980) and Nashville (1975) was first noticed by a producer on M*A*S*H, who hired him upon seeing his smoke-blowing short Pot Au Feu. In it, characters take a break from routine activities for a pacifying toke on a joint.

Pot au Feu was jimmied together for just $1000 over a couple of weekends in 1966, but was never officially released. Altman makes a cameo, lighting up during a chess game. He wasn't just some backseat marijuana activist, either. He served on the board of directors of the National Organization for the Reform of Marijuana Laws.

This extract comes from Ron Mann's upcoming documentary Altman, an in-depth look at the life and times of the my-way-or-the-highway auteur. Notorious for carving his own path, his films garnered a distinct style which culminated in the eponymous adjective "Altmanesque", which translates to mean dark humour, people talking over each other, and the occasional puff, puff, pass.

Altman is out in cinemas from 3 April