The Big Bang Theory is getting a very special guest on this Thursday's brand-new episode -- the legendary James Earl Jones!
ET's Rocsi Diaz recently paid a visit to the set, where the cast of the hit CBS comedy made no secret of their excitement at having the beloved actor on set.
"It's pretty insane to have James Earl Jones around at all," Jim Parsons (Sheldon Cooper) said. "He's just such an honest-to-God actor. ... There's no way ever you can even realize the amount of work he's done."
In a preview of the episode, Sheldon geeks out when he chances upon Jones in a restaurant, thanks to his legendary Star Wars role as the voice of Darth Vader.
And in real-life, Jones is a good sport about encountering die-hard Star Wars fans.
"Usually they have rows of posters they want me to sign," he told ET. "The young kids, I can't resist it. I have to do that."
Check out the video to hear why Jones is a big fan of The Big Bang Theory, and to hear Kaley Cuoco's reaction at having "the voice" at a table-reading of the script!
The Big Bang Theory's episode guest starring James Earl Jones, titled The Convention Conundrum, will air this Thursday, Jan. 30 at 8 p.m. on CBS.