THEY: Mysterious new FPS Q&A

THEY claims to be a "mystery first-person shooter" for PC, Xbox 360 & PlayStation 3. How do you create this feeling and what sort of techniques are used to provoke this sense of mystery?

The story-telling in THEY doesn't influence the fast paced action of a FPS game – it has dynamic battles, a living environment and those bad creatures you have to kill. But the story has some issues common with plots of mystery movies! After some analysis we figured out that one key element, which transports mystery is the so-called dualism and this is what we will show in THEY. On the one hand you have a real environment, which everybody knows (London) – on the other hand some mysterious phantoms and you don't know what they are. Another way is to build up characters' credibility during the storyline, you feel positive with them, you trust them – and suddenly something happens, which topples your big picture! This is what the essence of mystery is and it'll take some time to get an overall picture. For players this means, they have been aware of several surprises and nothing seems to be like it is in the beginning…