O’Brien is interviewed on set for Collider and talks about how his haircut almost cost him the role, the pressure of the role, and his friendship with co-stars. On his on-screen rivalry with Poulter:
It’s actually uncomfortable! We’re so funny. Even tonight, what we’re doing right now. We wrestle. He’s vicious. He’s scowling. He’s the antagonist of the movie and I’m the protagonist. Wes always says we’re opposite sides of the same coin, so we’re always supposed to be butting heads. Even after every take, he’ll go, “Are you okay?” I’ll go, “Yeah, are you?” He’ll go, “Yeah, but oh, I hit your knee!” And I go, “Yeah, my knee is fine! But how’s your elbow?” It’s just hilarious. We’re buddies off screen, as we all are.