Disney's Tron Legacy doesn't hit theaters until December, but already has a sequel is in the works.

According to Heat Vision, Lost writers/executive producers Edward Kitsis and Adam Horowitz have begun writing a sequel to the studio's sci-fi tentpole.

No details have been released because it is so early in the process. Insiders have suggested that Kitsis and Horowitz are working on a way to round the story into a trilogy.

No deals have been made with Tron Legacy director Joseph Kosinski or cast members to return, though options were placed in the original deals, and Disney surely would hope to reunite all the elements if Tron Legacy proves to be a hit.

No production date has been set.