Flatout 3. I just checked on steam, and it's tagged as "psychological horror". Being a fan of the first one, and still having spent lots of hours playing the second one, I was totally not prepared for the utter monstrosity of the third one
Never played 1, but I really liked 2. I didn't know 3 existed until now, and I'm having a blast reading the reviews. I think I might have to buy it (with the intention of refunding) just so I can experience the horror firsthand.