Brad Pitt signed up to star in new apocalyptic horror movie World War Z in a bid to please his zombie-loving young sons.
In the upcoming film, the Moneyball hunk portrays United Nations employee Gerry Lane, who travels around the world interviewing survivors of a zombie outbreak.
The thriller's premise is a departure from Pitt's most recent projects, and the 49 year old, who has three boys with fiancee Angelina Jolie - Maddox, Pax and Knox - admits he took on the role for the sake of his kids.
Presenting an extended look of World War Z at the opening night of CinemaCon in Las Vegas on Monday (15Apr13), he said, "Four years ago I knew nothing about zombies but now I consider myself an expert. This whole thing started because I just wanted to do a film my boys could see before they turned 18, one they liked anyway and they loved zombies.
"So we settled on Max Brooks' book called World War Z. We were faced with two Herculean challenges. How do we keep the global spectacular dynamic scope of the book and how do we originate a Zombie film that's been done quite often and really really well? What you are about to see is our answer to those two questions. We got a little carried away. I think you are going to like this as much as my boys are going to."