After the disappointment of the prequel trilogy there are those who greeted George Lucas's decision to step down as Star Wars head honcho last year with some degree of joy. Now Lucas's son Jett has revealed his father is still very much involved with production of the upcoming Episode VII, and keeps in almost constant contact with director JJ Abrams.

Speaking to Flicks and the City, the younger Lucas pointed out that George remains a creative consult in the wake of Disney's $4.05bn purchase of all rights to the long-running space saga in October. He said his father had been "very torn" by letting go of the series and had actually written outlines for future films.

"He's constantly talking to JJ," said Jett. "Obviously JJ was handpicked. He is there to guide, whenever, he'll help where he can. At the same time, he wants to let it go and become its new generation."

Jett said Episode VII would be based in part on original ideas handed by Lucas to Disney as part of the sale of LucasFilm. "I already know what happens," he said. "I'm happy with what's going to happen."

The younger Lucas confirmed that Saoirse Ronan had auditioned for a part on Episode VII but dismissed suggestions that the Irish actor might be joined by Britain's Benedict Cumberbatch, who played a villain in Abrams' Star Trek Into Darkness. "There's been rumours which I thought were pretty crazy," he said. "That some of the actors from Star Trek were going to play in Star Wars, which I know would never happen.

"I don't know if I would be so thrilled," he added. "I think that would be the beginning of the apocalypse if you were to cross Star Trek with Star Wars. I think that's a dangerous combination. Again, it would be interesting. It's an idea to explore if anything."

Abrams was revealed in January as the director who will take on Star Wars Episode VII, which is being filmed in London early next year. Disney plans to release a new trilogy of films, as well as several standalone origins movies which could bring back iconic characters from the original trilogy such as Han Solo, Yoda and Boba Fett.

Toy Story 3 writer Michael Arndt is overseeing the screenplay for Episode VII. The Empire Strikes Back's Lawrence Kasdan and Sherlock Holmes' Simon Kinberg will write two of the standalone "origins" films. The stars of the original trilogy, Mark Hamill (Luke Skywalker), Carrie Fisher (Princess Leia) and Ford (Han Solo), have all been tipped to return to the series.

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