Zombie Thriller WORLD WAR Z Undergoing Seven Weeks of Reshoots

Next summer's scheduled theatrical release for the upcoming adaptation of Max Brooks' popular survival novel, which stars Brad Pitt and Matthew Fox, is now in jeopardy as the project just undergo extensive production work.

World War Z is an adaptation of the critically acclaimed novel of the same name written by "zombie expert" Max Brooks (The Zombie Survival Guide). Director Marc Forster (Quantum of Solace) is helming the project from a script by Matthew Michael Carnahan. Last year Damon Lindelof (Lost) and Drew Goddard (The Cabin in the Woods) were brought on board to retool troublesome parts of the script.

Brad Pitt stars as the film's lead, named after the book's author, portraying a reporter who is documenting the outbreak and interviewing various people from around the world that tell of their encounters with the walking dead. Mireille Enos, Daniella Kertesz, James Badge Dale, Matthew Fox and David Morse also star

Paramount Pictures had recently moved the film's theatrical release date from December of this year to next summer in order to facilitate the release of the action thriller One Shot starring Tom Cruise. Now it's been revealed by unnamed sources within the studio that the production is undergoing a seven-week reshoot in London, England.

The decision came down after only 52 minutes of footage from the film's principle shoot was shown to executives, along with a few uncut action shots.

World War Z was slated for theatrical release June 21, 2013.