The film is based on a story by Greg Sestero about a road trip he took with Tommy Wiseau in 2003, during which Tommy thought Greg was trying to kill him.
This is the first project that Greg Sestero and Tommy Wiseau have appeared in together since the 2003 cult phenomenon The Room (2003).
Easter Egg: Just before Jon and his girlfriend are fighting in her apartment, a stack of DVD's are visible underneath the TV. One of the DVD's in the pile is The Room.
It was revealed at the Sep 30, 2017 screening at the Egyptian Theatre in Hollywood, as part of Beyond Fest, that the film would be split into two feature-length parts, referred to as Volume One and Volume Two. Only Volume One was screened at Beyond Fest, ending with the reveal of "Volume One" in the title and an abstract preview for Volume Two.
Director Justin MacGregor is a friend of Greg Sestero's. He saw The Room (2003) for the first time when he was 16 years old. Coincidentally, he and Greg met at the Rio Theatre in Vancouver, Canada - the same theatre where Greg and James Franco met for the first time and agreed to turn Greg's memoir into The Disaster Artist (2017).