Brad Pitt In 'World War Z' Trailer: Watch Now!

The zombie apocalypse is officially on, and this first preview will show you how it starts.

After quite a long wait, we have finally set our eyes on at least some piece of the ginormous zombie flick, "World War Z," starring Brad Pitt. The only thing that might seem confusing about the teaser trailer is the "zombie" part.

The hordes of sprinting crazies are never identified as the undead, brain chompers that we've grown very familiar with in the last few years, but the teaser trailer curiously never even hints that the masses might be zombies. But as this is an adaptation of the book by famous zombie author Max Brooks and the "Z" stands for "zombie," you can rest assured that the undead will make an appearance in the movie.

Aside from that, what will certainly strike you about "World War Z" even from the trailer is the sheer scale of the thing. We start simply, as most of these movies do, with Brad Pitt as Gerry Lane, a U.N. employee, as he sits in his car with wife, played by "The Killing" star Mireille Enos, and two daughters. Soon, their guessing game in the car turns dark when helicopters begin to circle and the street ahead of them explodes.

From there, the war against the zombie horde begins, and Lane is asked to play a vital role in assault against the undead, having to leave his family behind. The scale on which "World War Z" is working is largely new for the genre, which tends to focus on a small group of survivors holed up in a shopping mall or country house. Here, we get a tower of bodies piling up to scale a wall instead.

"World War Z" comes from director Marc Forster, who previously directed "Quantum of Solace." Reports of extensive reshoots and a number of rewrites made headlines after the movie was pushed from its initial release in December of this year. It is now scheduled to open in theaters on June 21.

Check out everything we've got on "World War Z,"