You probably know that Joss Whedon’s production company is named Mutant Enemy. But did you know where the name comes from? Whedon, the creator of Buffy the Vampire Slayer and Firefly, is a huge fan of the prog rock group Yes, and he chose that phrase as a nod to the band and their song “And You and I.” That’s just one of the facts featured in the latest episode of You Think You Know Movies!

Whedon cites Kitty Pryde, longtime member of the X-Men, and his primary inspiration for his most famous creation, Buffy the Vampire Slayer. (Whedon later wrote a critically acclaimed run on the Astonishing X-Men comic.) Whedon and director Drew Goddard wrote the script for their horror satire The Cabin in the Woods in just three days. Three days! Think how many scripts you could write in your lifetime if you wrote them in just three days. We are all such slackers.

‘You Think You Know Movies?’ is a ScreenCrush original series that dives deep into the cinematic worlds of your favorite movies and freeze frames a few tidbits you might not have known. We’ve already tackled Star Wars, The Avengers and Spider-Man, but now we’re covering the life and times of the man who directed The Avengers and Age of Ultron, Joss Whedon. Watch more installments of ‘You Think You Know Movies?’ below and let us know in the comments what movies we should cover next.