While often scorned (aaaaand sometimes for pretty good reason!), improvisational comedy gave birth to nearly all your favorite movies and TV shows, and it’s where your most beloved comic actors got their start. Amy Poehler, Tina Fey, Bob Odenkirk, John Belushi, Bill Murray, Kate McKinnon, Nick Kroll, Stephen Colbert, Aubrey Plaza… all these and many, many more kicked off their careers and trained with such famous improv troupes as Second City and the Upright Citizens Brigade. But the concept and practices of longform improvisational comedy in its current form sprung from a single, deranged person that you’ve possibly never heard of: Del Close.

In the documentary For Madmen Only, director Heather Ross attempts to dig deep into the life and mythos of this seminal, mysterious figure, and the result is just about as messy as Close himself. (But that’s not always a bad thing!)

The central problem with creating a definitive history of Close is that a) he’s dead, b) much of what is known about him comes from a surreal comic book, and c) he kind of lied a lot. As legend has it, Close ran away to join the circus at an early age (probably true), witnessed his father kill himself (probably not true, but the dad did die by suicide), partnered with early improv founders Elaine May and Mike Nichols (true!), was addicted to drugs (true!), became a guru to scads of now-famous people at Second City, though never fully recognized for his influence before eventually dying of emphysema and donating his skull to Chicago’s Goodman Theater for their productions of Hamlet (true, true, true, and false—it wasn’t his actual skull).

Close practiced an Andy Kaufman-esque style of comedy that promoted getting to the “truth” of every action, always making the unexpected choice, and saying “yes, and...” to the choices made by one’s scene partner. However, his very intense personality and drug addictions probably stalled any attempt at the fame that was achieved on a regular basis by his students. Ross’ documentary neatly captures Close’s talents and foibles during interviews with well-respected improvisers such as Bob Odenkirk, Tim Meadows, Adam McKay, Dave Thomas, and more—though I must admit some disappointment from only seeing fleeting glimpses of Poehler, Fey, and other comedic faves.

Where the documentary hops off track is when it puts far too much emphasis on the comic book “autobiography” of his life, DC’s anthology series Wasteland. A surrealistic mind-fuck of a horror comic, it’s such an exaggerated retelling of Close’s life that it’s not much use for anything other than a strange peek into the author’s id. Ross also stages dramatic reenactments of Close and Wasteland’s co-creators (competently portrayed by James Urbaniak, Matt Walsh, Patton Oswald, Paul Scheer, and more), but it never quite works as well as one would hope, and comes across more as filler than anything else.

Still, I believe Ross did the best she could with the little source material that’s available, and if one is interested in the bones of improvisation and how modern comedy came to its current fruition, this doc is a good starting place—and Del Close is more than a worthy subject.

Here’s how you can stream For Madmen Only as part of the Portland International Film Festival.