The game takes place in France in the mid-Sixties. The story, mood, and style of the game are inspired by the city of Paris, Belgian comics and Sixties cinema.

The late teen tomboy Monique lives as a cat burglar in Paris. After a heist gone wrong, she ends up in jail where she meets an enigmatic prisoner. They escape prison together, and agree to venture on a spectacular heist for a precious diamond. Thus begins a quest that takes our heroes through a catholic monastery, a Parisian metro station and the Catacombs.

The game focuses on story and atmosphere. The gameplay mixes elements of stealth, discovery and puzzle solving.