Pathologic

In Pathologic, you'll follow three outsiders who arrive in a contaminated town. Each party member--a highly educated bachelor, a farsighted Ripper, and an eccentric girl--must survive the horror and play a vital role in the fate of the doomed town. The town constantly changes and reacts to your behavior and random circumstances. To battle the omnipresent enemies, you must develop a variety of individual survival and resource-hunting strategies. The game's three heroes act independently--when you play as one character, the two rejected heroes plot against you.

You play one of three characters (I've played Batchelor, the easiest - which is short for "Batchelor of Medicine" and in turn says volumes about the language/atmosphere in this game) and they all have different roles in the unfolding story. In fact you can't play the girl (Devotress) until you've played at least one of the other two (the other is Ripper - a surgeon). The game has a fixed length because it's sort of real time (speeded up that is, an hour of game time is about five minutes real-time) and, as the game reminds you at the start of each of its days, there are twelve days to survive. There's a bit of combat, but it's mostly a quest and story thing. With constant marching around the town (and examining trash cans).

The game claims to adapt to the choices you make and to have multiple different endings. Having got through as one character, I believe this to be true. I think it gives you more freedom than any other adventure/mystery game I've ever seen and it means that faq designing is very difficult (although the makers do have one on their website).

The controls are keyboard and mouse. The mouse is the viewpoint and it can be clicked in fights and to select objects. The keyboard controls other things including movement, quest notes (a symbol comes up on the screen when this is added to), letter-reading (new letters bring up a symbol on your screen, but no other prompts to read the important communications), inventory, sneak and a few others (I never found a use for jump, but that may say more about me). They're fine to use, but I found I had my finger down on W (move forward) an awful lot. Also, it's well worth returning to the manual after the first day or two to check that you're not missing anything.