Like many great comedians including Robin Williams, Rickles was trained as a serious actor and he had many such roles in film and TV. One that stands out for me is a scene from the play
Inherit the Wind, based on the historical Scopes Trial, that he filmed with Jack Klugman and which appeared on his otherwise comedic 1975 home video release with the fitting but orthographically incorrect title
Buy This Tape You Hockey Puck (I didn't obey Rickles' injunction but instead saw the clip on TV somewhere). They did the scene near the end of the second act where Klugman, playing the role based on the real-life attorney Clarence Darrow, is cross-examining Matthew Harrison Brady, based on William Jennings Bryan and played by Rickles. In contrast to his New York City and Jewish roots, Rickles gives an amazing performance as the beleaguered Midwestern populist and fundamentalist Christian Brady, mocked and humiliated by the Klugman character for his smug, uncompromising religious beliefs ("The Gospel according to Brady! God speaks to Brady, and Brady tells the world! Brady, Brady, Brady, Almighty!") which are increasingly at odds with the science and modernity. The scene closes with Brady beginning to recite in order the names of the books of the Bible and his voice trailing off at the end into despair, a striking portrayal of a hoary man finally recognizing the ebbing of the relevancy of his faith and his own significance, which Rickles conveys with a pathos surprising for anyone who's witnessed his acerbic comedic wit.
Of course, my favorite "serious" role of his was Norbert Wiley, the oleaginous hood who--as the latest in a board series of characters--gets temporarily shipwrecked with the castaways in
the Gilligan's Island episode "The Kidnapper." A memorable turn not for the least reason that Ginger, Mary Ann and Mrs. Howell get tied up in this episode (though only "Lovey" on camera, but just the thought of Ginger in bondage was enough to stimulate my deviant boyish imagination, and
her and her helpless high heels strapped to Dr. Balinkoff's rack in another episode set it off to new "heights").