The Sinking City is a Lovecraft-inspired adventure set in '20s America. It's got an open world, but the devs are most excited for their open investigation system, which'll see us hunting down clues without checklists or quest markers. There are monsters, too, so while "the game is not about fighting monsters," and is focused on investigation, you'll still have to defend yourself.
The Sinking City doesn't yet have a release date. It comes from developer Frogware, which has a history of detective games, most recently Sherlock Holmes: The Devil's Daughter. We'll have the full segment from the PC Gaming Show posted here soon.