You are Roy History, a G.I.E.S.T. (General Investigator of Extranormal Solids and Truths), inhabiting a muted, ghostlike world at the end of history.  You are sent to investigate various  buildings that hold S.P.I.R.I.T.s (Solid Past Imprints Retained In Time). The main mechanic of the game is played after you discover a polaroid camera SPIRIT that you can use to briefly walk in the solid world where the SPIRITs originate from, one in which solid artifacts and beings from that past continue to live on. It also allows you to solve puzzles that unlock secrets about the lost world as you venture from each investigation site.