He guest-starred in several other television series, including the premiere of the original Battlestar Galactica. His film roles include that of the Soviet brainwasher Dimitri Gomel in the 1962 political psycho-drama The Manchurian Candidate, which also had work for TOS guest actors Leslie Parrish, Whit Bissell, and James Gregory. His most famous film is probably Alfred Hitchcock's The Man Who Knew Too Much (1956). He also made a small appearance in Italian director Federico Fellini's Casanova in 1976. Nalder died of bone cancer in late 1991.