These days, a lot of TV actresses are taking on dual roles: The Vampire Diaries' Nina Dobrev (Elena/Katherine), Ringer's Sarah Michelle Gellar (Bridget/Siobhan) and The Lying Game's Alexandra Chando (Emma/Sutton). But back in 1963, Patty Duke was all on her own as identical cousins Patty and Cathy Lane on The Patty Duke Show. "We didn't have digital anything," recalls Duke, 64. "We'd [shoot] the Patty side first, then everyone would stand in place while I sneaked off and came back dressed as Cathy. In postproduction, they would actually split the celluloid."
Tonight Duke is returning to TV for a guest appearance on Hawaii Five-0. It's a role she couldn't turn down. "I play a woman in the second stage of Alzheimer's whose son was involved in a nefarious deal with gold coins in the ocean," says Duke, who took home the best supporting actress Oscar for The Miracle Worker in 1962. "McGarrett [Alex O'Loughlin] and Lori [Lauren German] come to inform my character that her son is dead and find that I'm living 20 or 30 years in the past. In her head, [her] son is still a boy coming home from school any minute for a sandwich."