Matthew Morrison, who directed the festive special, reveals not just anyone can play Han Solo's hairy friend - and TV producers needed Lucas' blessing to contact the movie mogul's chosen Chewie.
Morrison, who also plays teacher Will Schuester on the hit show, says, "He (Lucas) gave us Chewbacca. There's only one guy who can officially be Chewbacca and he lives in northern California; they flew him in... It was just great... We were all taking pictures with him.
"He's a guy who has been doing it for 12 years."