'Back to the Future' Star Christopher Lloyd Is Coming to 'Big Bang Theory' for a Mysterious New Role!

Christopher Lloyd is traveling to The Big Bang Theory!

ET has learned that the legendary Back to the Future actor will be guest starring on the Dec. 1 episode of the smash CBS comedy. No details about Lloyd's character or storyline have been revealed, but we're keeping our fingers crossed that some time-traveling puns and Doc Brown references will be thrown into the mix.

"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 executive producers said in a statement on Wednesday.

MORE: 'Big Bang Theory' Spinoff About Young Sheldon Reportedly in the Works

This casting news comes just days after reports that a Big Bang Theory spinoff is reportedly in the works. The project is said to center on Sheldon Cooper’s childhood and family growing up in Texas that have been referenced on the flagship series.

Jim Parsons, who plays Sheldon, is reportedly attached to executive produce the proposed spinoff, alongside creator Chuck Lorre and showrunner Steve Molaro.

The Big Bang Theory airs Thursdays at 8 p.m. on CBS.