Revenge of the Sith might've capped off George Lucas' controversial Star Wars prequel trilogy, but it wasn't the end of Lucas' plans for the Star Wars universe. In 2008, Lucas launched Clone Wars, an animated series set between Attack of the Clones and Revenge of the Sith, and assembled a crack team of writers and producers to develop a live-action series called Star Wars: Underworld.
From 2008 to 2010, Lucas and his writing team cranked out 50 scripts—about two seasons' worth of material. According to Lucasfilm producer Rick McCallum, Underworld was a dark and gritty crime drama reminiscent of The Godfather and Deadwood. Game developer Corey Balrog, who read some of the scripts, claims that a tragic love story between The Emperor and a "hardcore gangster" was a major plot thread.
Reportedly, Lucas wanted to hold off filming until television special effects were advanced enough to support his vision, and Underworld was put on hold. Then Disney happened. In 2012, the studio bought Lucasfilm and Star Wars from Lucas for a cool $4 billion and immediately started working on its own set of Star Wars projects, including The Force Awakens, Rogue One, and Star Wars: Rebels. While Lucasfilm president Kathleen Kennedy claims that Underworld might still see the light of day, at the moment, the property is dead and buried.