The rumors of a Left for dead Prequel are not true. I can see where people thought it WAS a prequel, also considering in the youtube description it said- " Have you ever wondered how the Left 4 Dead series began? It started with a heist! " But it is just DLC for payday the heist. It opens u with you and a few other guys walking into... Mercy Hospital. It isnt going to be its own game but you can see some easter eggs. This is what the mission is going to be like. Aparently someone who your looking for is in Quarintine ( and aparently I assume is infected ) and you got to get him out. And it looks like the patient is under Goverment control. And at the end of the videoyou can hear someone say " You * static * left for dead " The first time I saw t I realised it was for Payday because the design, voice acting, weapons, and such. Anyhow it is interesting and makes me want to buy Payday. Here is the video. http://kotaku.com/5918886/valve-is-making-a-left-4-dead-prequel-after-all