marc mar maron! >> i've been doing stand-up comedy for more than half my life, is that it?y graduate work for chopping lines of cocaine for sam kinison. >> reporter: highs and lows he brings out interviews. >> it seems like you're part journalist, part therapist and part kindred spirit. >> yeah, i don't consider myself a therapist, but i've had to do that. >> reporter: in one accept society, he confronts carlos mancia on joke stealing. >> is there a chance you don't know you're doing that? >> with openers, possibly. >> and then you kind of went easy on ben stiller. i'm not interviewing war criminals here. >> reporter: at other times, he's more of a father confessor. norm macdonald told him about his struggles with gambling addiction. rainn wilson told him about his baha'i faith. in 1995, maron shared a magazine spread with louis c.k. and sarah silverman. they went on to do big things. maron didn't. >> oh, my god, marc maron. >> reporter: and that led to a long-staing feud between maron and louis c.k. just this week -- >> thank you. >> what's up? >> there's a history there,