Brad Pitt made a special on-stage appearance at a special preview screening of his new movie World War Z at CinemaCon this week. Introducing new snippets of the zombie-thriller to a packed house in Las Vegas, Pitt revealed that he agreed to making the movie to give his boys something good to watch before they turn 18.

Speaking about the scope of the big-budget production, directed by Marc Foster, Pitt told the gathered audience, "So we settled on this book, 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 genre that's been done quite often and done really really well. What you're about to see is the answer to those two questions. We got a little carried away." 

Watch Brad Pitt Introduces 'World War Z' Video Below

World War Z began principal photographer in July 2011, in Malta, though filming moved to Glasgow, Scotland, in August with around 2,000 extras taking to the streets. Scenes were also shot in Falmouth, Cornwall. The movie stars Pitt as a United Nations researcher in the midst of a zombie apocalypse. A script leaked to Ain't It Cool News in 2008 led the movie news site to call it "a genre-defining piece of work that could well see us all arguing about whether or not a zombie movie qualifies as Best Picture material."

An extended trailer for World War Z was released earlier this year. Watch it below:

 

World War Z hits theaters in the U.S. on June 21, 2013.