John Ratzenberger
Two years before making his first appearance as Cliff Clavin on the NBC comedy series Cheers, John Ratzenberger played Rebel Force Major Bren Derlin in The Empire Strikes Back.
In the movie, Major Derlin served as the operations and security chief at Echo Base, the Alliance headquarters on the planet Hoth, under the command of General Carlist Rieekan (Bruce Boa).
