You wake up in the world, what is being called world between life and death. It is up to the people themselves to fight for survival. But this world isn't empty, it is magical world and it is owned by someone who is being called death. Apparently he isn't god of this world and can only manipulate everything. So you escape from him but at the same time you go through your dark past, so you would understand, why and how did he end up there.
If you have played CS "The Interrogation Chapter 1", you probably remember this map. There was note where was written how beatiful this map looks like during the day... Damn straight it does!