Matt Damon and Cillian Murphy in Berlin in February.
CNN  — 

Cillian Murphy doesn’t want to be distracted from his roles.

His “Oppenheimer” costar Matt Damon recently told “60 Minutes” that Murphy is “worst dinner companion imaginable”

“What he meant by that was when you’re working on a film, when you’re being the character, there’s very little room in your head for anything else,” host Scott Pelley told Murphy.

“I’ve always been like that, I think,” the “Peaky Blinders” star replied. “It’s because, to me, you have the time on set, which is a short enough time. You have 10 hours, maybe. And then the other part, if you’ve got a significant part, you’re having to keep your lines fresh.”

Murphy said he also needs his rest.

“And then the other big thing for me is sleeping. I love sleeping and I need sleep,” he said.

But, he adds, when he’s not working, he does enjoy his outings with Damon.

“I’ve had lots of lovely dinners with Matt Damon since the movie has finished, and we’ve been out promoting it and stuff,” he said. “At the time, yeah, you just don’t have the room, in your head and you want as much sleep as possible.”