Back to the Future star Christopher Lloyd, who played Doc Brown in the time-traveling film trilogy, will guest-star on an episode of the CBS comedy The Big Bang Theory.

　　According to Entertainment Weekly, Lloyd will appear on an episode that airs on December 1. It's not known at this point if he'll be playing himself on the show, as Wil Wheaton has done in the past. The plot of the December 1 episode is also a mystery for now.

　　"We're so excited to be working with Christopher Lloyd, and think we've created a fun part that fans will really enjoy," The Big Bang Theory producers told Entertainment Weekly.

　　Lloyd will also appear in an episode of Syfy's 12 Monkeys for the show's upcoming third season.

　　Numerous celebrities have guest-starred on The Big Bang Theory over the years, including Bill Nye, Bob Newhart, Charlie Sheen, Steve Wozniak, Stan Lee, and Katee Sackhoff, among many others.

　　The Big Bang Theory is one of the most popular TV shows today in terms of viewership, as the show regularly attracts over 20 million viewers a week. It is currently on its tenth season.

　　Just this week, it was reported that CBS is working on a prequel spinoff that is described as "Malcolm in the Middle but with a young and potentially teenage version of Sheldon."

　　Disclosure: CBS is owned by GameSpot parent company CBS Corp.