'World War Z,' the futuristic zombie movie starring Brad Pitt, has largely received positive reviews from critics, and the film is expected to draw $45 million in the U.S. in its opening weekend, Boxoffice.com reported.

A majority of reviewers have termed the movie "smart" and "refreshing," and pointed out that Pitt’s appeal with the international audience will work in favor of the movie, which released six months after its initial release date due to complications with increasing production costs.

Changes to the movie’s script, which were initially predicted as a factor for the film’s downfall, are now expected to help 'World War Z' do well when it opens nationwide Friday, according to Bloomberg.

"After the first pass at the movie we found the final 20 minutes were not consistent with the rest," Paramount’s vice-chairman Rob Moore told Bloomberg. "And by putting together a great group of people, they were able to craft something that lived up to the rest of the movie."

'World War Z' is based on Max Brooks’ 2006 novel of the same title, and although the movie has diverged from the source material, critics favored the final product.

Rotten Tomatoes, a website that aggregates reviews, gave the movie an average rating of 6.3 on 10. "World War Z still brings smart, fast-moving thrills and a solid performance from Brad Pitt to the zombie genre," the website said.

The New York Times called the movie's climax "genuinely suspenseful" and Variety magazine praised the Marc Forster-directed flick as a "smart, gripping and imaginative addition to the zombie-movie canon," predicting that the movie will do well as it is an "unusually serious-minded summer entertainment."