The action takes place in the early twenty-first century. The main character, an employee of the American special services Morgan Sinclair, receives an order from her dying father to go to the most famous French museum to "borrow" (illegally of course) four magical artifacts (the so-called "keys of satan"), with which evil people are allegedly able to arrange the real end of the world. In the Louvre, the girl meets a Templar spirit, who introduces himself as Guy de Sombreval. The conversation with him finally brings some understanding of what is happening - it turns out that some "black templars" really decided to lead to the apocalypse and must be stopped by finding four items: lion, demon, eagle and bull statues. To do so, Morgan mysteriously needs to visit the Louvre in three different eras: 1377, 1610, and 1770.

The basic gameplay consists of puzzles of finding and then using items correctly - often quite complicated and requiring the sharing of found items, including even real spell scrolls. The difficulty is further increased by very non-obvious lethal threats - sometimes it is enough to take the wrong step in the wrong direction or touch what is not allowed and the game ends immediately, without any hints that it should not be done.