Speaking on radio station ZM, Keery gushed about working with Waititi: "Oh my gosh, that handsome guy is amazing. He's so, so talented. Every day I show up on set and be like, 'are you sure I'm supposed to be doing all of these scenes' because he's amazing.
"That guy is not afraid really of anything, he has no fear on set and he's down to try anything and every single take is different. You know, it's really just like a learning experience about being confident on set and, yeah, I felt like I learned so much and picked up so much from him."
The ZM hosts joked his answer was the perfect ploy to get him cast in Waititi's next big project.
He added: "You guys know him, right?"
Known for his luscious locks, which he chopped off to the disappointment of his fans, Keery joked that he and Waititi bonded over their hair on set.
"We'd just sit across from each other in stools and pretty much just touch each other's hair for a couple of hours just to get into character," Keery says.
"I didn't really want to do that but he was just sort of insistent," he added.
• Free Guy is in cinemas now. Watch ZM's full interview with Joe Keery above