The storyline, like many zombie films, feels stretched thin and doesn't entirely hold up under scrutiny, even if you’re willing to accept the idea of zombies existing. However, that's generally something people who enjoy zombie movies are prepared for. It follows a familiar formula: zombies created by a virus spreading quickly across the globe. I found the story hard to believe, especially compared to earlier depictions of zombies where there was usually some supernatural or magical explanation—I actually preferred those better than this virus idea because it has too many unanswered questions. For instance, it’s difficult to imagine a virus could keep bodies moving around without sustenance inside a lab for any length of time. But then again, it is a zombie movie, so you have to overlook these problems. As an action film featuring zombies as the antagonists, it's actually pretty good. The action sequences are well-done, the special effects are acceptable, and the pace moves along at a good clip. Pitt gives a solid performance too, although most of the other actors aren’t particularly memorable. I thought the scenes where the zombies climb over each other to get up walls or reach helicopters were pretty neat. It isn't overly graphic for a zombie movie, which might be a positive thing depending on your taste; personally, I like some gore in these kinds of films. There are a few frustrating elements that seem almost mandatory in Hollywood productions. For example, the world is facing total destruction and Lane and his wife simply don’t want to participate—seriously? And why do characters always allow their children to wander off when they should be keeping an eye on them? Not to mention how awkward people become when trying to sneak around quietly. These things just pull you out of the experience. Ultimately, the movie succeeds in providing two hours of action-packed entertainment that isn't meant to make you think too hard.

Source on TMDB