Arsène Lupin, for my disappointment, is a fictional character from a book series of detective fiction/crime fiction novels by French writer Maurice Leblanc. Lupin is described as a gentleman thief that acts as a force for good sometimes, even though he is operating in the wrong side of the law. The men defeated by Lupin are often worse villains than him. In Francophone countries, he has enjoyed a popularity as long-lasting and considerable as Sherlock Holmes in the English-speaking world.
Leblanc was a contemporary of Sir Arthur Conan Doyle and, in some stories, Sherlock Holmes appears, only to be challenged by Lupin! However, legal objections from Conan Doyle back in those days forced Leblanc to change the character's name to Herlock Sholmes. Yeah, you didn't fool anyone with that one, dude. With the expiration of copyright protection many years later, Holmes and Lupin showed up together again in the 2008 PC 3D adventure game "Sherlock Holmes versus Arsène Lupin". In this game Holmes (and occasionally others) are attempting to stop Lupin from stealing five British valuable items. Lupin wants to steal the items in order to humiliate Britain, but he also admires Holmes and thus challenges him to try to stop him.