If a new rumor is to be believed, Robert Downey Jr. is joining the cast of Assassin's Creed as famed inventor Leonardo Da Vinci, alongside Michael Fassbender. The rumor originated at MoviePilot, although the story has since been removed.

The story went on to claim that the Assassin's Creed plot is based on the second video game in the series, Assassin's Creed II, where the inventor appeared alongside the game's main protagonist, Ezio Auditore.

We reported last month that the Assassin's Creed II game will serve as the basis for the adaptation, with star Michael Fassbender playing two distinct characters in different timelines. In present day, the actor will play death row inmate Michael Lynch, who becomes a pawn in a longtime war between the Templars and the Assassins. He becomes subjected to a number of tests by an evil scientist named Joseph, although Michael gets help along the way from a character named Lara. Michael Fassbender is also playing an assassin named Aguilar de Agarorobo in scenes set during the Spanish Inquisition.

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Justin Kurzel, who worked with Michael Fassbender in the upcoming Macbeth, is directing from a script by Scott Frank, Michael Leslie, Adam Cooper and Bill Collage. It isn't known when production will get under way.