Dedicated with love and gratitude to Robin Williams, Kevin Pollak’s documentary convenes some five dozen talking heads to discuss the commonsense correlation between emotional anguish and funniness. Talking is all the movie is, and although a lot of the talkers are comedians, the discussion itself isn’t necessarily funny. Nor for that matter is it very focused — there’s no consensus on how much if any misery comedy actually requires, for instance — but that’s sort of okay because if the surest way to ruin a joke is to explain it, imagine the epic ruin of explaining all jokes. Pollak isn’t taking a solve-for-x approach here so much as simply geeking out with his fellow tribesmen (and a few women), who may or may not be your favorite funny people anyway. You might even argue with the presumption that some of them are funny at all. As an offscreen questioner, Pollak probes only gently, but there is a perceptive intelligence at play in dovetailing origin stories, anecdotal minutiae, and offhand self-analysis from the likes of Judd Apatow, Larry David, Jimmy Fallon, Tom Hanks, Marc Maron, and Amy Schumer. They do seem to agree that it feels really good to have control of a room.