While Interstellar may not have been The Second Coming, director Christopher Nolan’s sci-fi epic was an astoundingly ambitious piece of work that resulted in some undeniably jaw-dropping sequences. The filmmaker is famously secretive when it comes to his projects, and since Interstellar had its fair share of surprises in store for audiences, Nolan’s pre-release interviews were understandably vague. The opportunity to be privy to a post-release interview with Nolan about the film—during which he can be candid about its secrets—is exciting enough, but how about throwing in another incredibly talented filmmaker into the mix as the interviewer?

Early last month, Nolan participated in a post-screening Q&A about Interstellar at the Aero Theater in Santa Monica with Looper, Brick, and the upcoming Star Wars: Episode VIII writer/director Rian Johnson acting as the moderator. Audio of the Q&A portion has now made its way online, and it’s a must-listen.

During the discussion, Nolan talks about how he executed the film’s tesseract sequence using projectors so that Matthew McConaughey was actually manipulating images of Murphy’s bedroom on-set. He also discussed being jealous of his brother writing the film for Steven Spielberg, his unique collaboration with Hans Zimmer on the score, making a profit from the corn they grew for the film, and the reasoning behind casting someone as recognizable as Matt Damon as Dr. Mann and keeping it a secret.

It’s a really fascinating listen for anyone at all interested in filmmaking. Listen to the audio recording below by TheBigKahoona, via Rian Johnson’s Twitter.