The new video game World War Z is inspired in part by the 2013 Brad Pitt movie of the same name. Despite the film being about six years ago, the new game is selling very well. Developer Saber Interactive and publisher Focus Home Interactive announced today that the co-op shooter has reached more than 1 million copies sold in its first week since launching on April 16 for PS4, Xbox One, and PC.

Saber CEO Matthew Karch said the studio is "humbled and thrilled" by the game's "immense success." He specifically called out the PC edition as doing especially well. Released as an Epic Store exclusive, the game sold 250,000 copies on PC alone and that success was due in part to the "tremendous support" Epic gave Saber, Karch said.

"Moving forward, we'll continue to expand the game and its community with new improvements, stability updates, and bonus gameplay content, beginning very soon with a special new mission for the Tokyo episode," Karch said.

World War Z runs on Saber's own "Swarm Engine," which is capable of rendering "hundreds" of zombies on screen at once. In the game you play as one of six difference classes in four-player co-op missions set in places like New York, Jerusalem, Moscow, and Tokyo. In addition to fighting against zombies, World War Z features multiplayer support for team-based PvP.

World War Z is a budget-priced game, coming in at $40 USD on PS4 and Xbox One, and $35 USD on PC. It's only available digitally.