Brad Pitt made three appearances at separate airings of new film World War Z yesterday (June 6), surprising fans across North America as he showed up in Philadelphia, Atlanta and Chicago all in one busy day. The actor might even surprise a few more audiences around the country for the remainder of the week as the film continues to perform to packed-out crowds across the country.

Pitt, who attended the premiere showing of the film in London last Sunday (June 2) with his wife Angelina Jolie - who was making her first post-surgery appearance in public, turned up unannounced at the AMC River East in Chicago yesterday evening to introduce the shocked fans to the new movie, having done the same thing a little closer to the eastern coastline at cinemas in Philadelphia and Atlanta that morning. Pitt spoke briefly about the film and thanked the movie-goers for coming down to the showing.

In the film, Pitt plays family man and UN worker Gerry Lane who, after the breakout of a world-wide zombie pandemic, is forced to join up with a team of experts trying to save the world before it is too late, with Lane forced to travel the globe in a bid to discover the weakness of the zombie menace before it is too late.

The movie, directed by Marc Forster and based on the Max Brooks novel World War Z: An Oral History of the Zombie War (screenplay by Damon Lindelof and Matthew Michael Carnahan) is in US cinemas now and hits UK cinemas June 21. Check out the trailer here.

Watch exclusive footage from the movie in the new Muse video 'Isolated System'

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