Over 20 years ago a friend said to me, "You really ought to catch this film Roger & Me. It's by a guy called Michael Moore and it's a very funny documentary about the closing of the GM motor works in Flint, Michigan."
This sounded most unlikely to me. Documentaries were rarely funny at the time, and the subject matter didn't seem to lend itself to humour. I went expecting something worthy but probably dull.
How surprised I was. Moore's film was indeed funny, angry, unusual and utterly devastating all at one time.