http://www.pcgamer.com/metal-gear-survive-shows-off-single-player-base-defence-january-beta-to-skip-pc/

Metal Gear Survive is the first post-Hideo Kojima Metal Gear game that's due on February 20 in the US and February 22 in Europe. Tim went hands-on with its multiplayer component at this year's E3 and enjoyed it—and publisher Konami has now dropped a new five minute-long video that focuses on the game's single player campaign.

Despite being a Metal Gear Solid 5 spin-off, the following short explains that Survive immediately follows Ground Zeroes, and that the protagonist is one of the soldiers present on Mother Base at that time. He's been pulled into a wormhole, we learn, before being spat out into an alternate world by a "mysterious organisation" six months down the line. It's in this odd dimension where the the game's Wanderer zombie-likes live.