Emerald City Confidential.

Dave Gilbert has released his latest game [for Windows], the fantasy/noir/beloved-public-domain-story themed Emerald City Confidential. Set in L. Frank Baum's OZ, well after the events of most of the best known stories, it is again an adventure game, and while there seems to be a little more in the way of inventory management this time, the writing remains sharp, and the puzzles compelling.