'Star Wars Rebels': David Oyelowo, Freddie Prinze Jr. in Talks for Voice Cast (Exclusive)

Freddie Prinze Jr David Oyelowo Split - H 2013
<p>Freddie Prinze Jr David Oyelowo Split - H 2013</p>   |   Getty Images
"Rebels" is due to air on Disney XD starting in fall 2014.

While most eyes have been on the casting of Star Wars: Episode VII, another franchise player set in the galaxy far, far away has been quietly operating under the radar.

Star Wars: Rebels is the CGI-animated series being made by Lucasfilm Animation that will air on Disney XD.

THR/HeatVision has learned that David Oyelowo, Freddie Prinze Jr., Vanessa Marshall, Taylor Gray and Steven Jay Blum are in the process of being cast as the voice leads for the series, which will make its debut in fall 2014.

Little is known about the series other than it is set during the time period between the two trilogies, as the Empire expanded its reach and Luke Skywalker was growing up on Tatooine.

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Simon Kinberg (X-Men: First Class), Dave Filoni, who worked on the previous Star Wars animated series Clone Wars, and Greg Weisman (Young Justice) are executive producing.

Oyelowo is currently starring as Forest Whitaker's son in Lee Daniel's surprise $100 million hit The Butler and is shooting Interstellar for Christopher Nolan. His name surfaced in connection to the Star Wars universe in a report by Latino Review -- although it had him pegged for the film side. (Not that this precludes him from any film appearance, by the way.)

Prinze is best-known for playing Fred in the live-action Scooby Doo movies but has done voice work for the Mass Effect video games. Sources have said Prinze is a big -- and genuine -- Star Wars fan.

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Marshall has done of plenty of superhero voice work, notably as Black Canary in Young Justice, Black Widow in The Avengers: Earth's Mightiest Heroes, and Wonder Woman in Justice League: The Flashpoint Paradox.

Gray is a relative newcomer to the voice scene and may be known for starring in Nickelodeon's short-lived show Bucket & Skinner's Epic Adventures.

Blum voiced Starscream in Hub Network's Transformers Prime as well as Lex Luthor in Flashpoint Paradox. He also works plenty in the video game world, with Call of Duty: Origins and God of War: Ascension among his credits.

When asked for comment, Lucasfilm said: "We don't have any casting announcements at the time but are excited about the series and look forward to sharing news with you in the future."