Diabolik: The Original Sin is an adventure game based on the character Diabolik; an Italian comic book character known as the "king of terror" and "the perfect thief". The player controls the "Robin Hood"-character Diabolik, as well as his girlfriend "Eva Kant", and briefly some other characters in a few chapters. The Original Sin refers to a valuable painting which Diabolik is forced to steal as his girlfriend is held captive as a hostage.
The gameplay combines a standard point and click interface with a stealth system, requiring the player to act quickly in order to succeed. The game also features some action elements that demand fast reflexes. Using 3D characters on animated backgrounds, Diabolik: The Original Sin has comic book-like animations.