Hidden Mysteries: Notre Dame is an interactive hidden object adventure game set in Paris at the Notre Dame Cathedral. The Crown of Thorns, the most precious and revered relic there has disappeared. As chief investigator assigned by the Prfecture de Police, the player will uncover the hidden secrets of Notre Dame de Paris.During the course of the investigation, the player encounters the spirits of historical and fictional characters associated with the cathedral. The spirits are encountered through documents, clues, flashbacks and even good old fashioned hauntings. Each spirit has a unique motive to steal the crown but of course could not have stolen it in present day reality.