His size (7-foot-2) made him a good actor to play monster-like characters. He is memorable in the shitty early sixties film Eegah, and truly unforgettable in what is perhaps the most famous Twilight Zone episode ever, "To Serve Man."
Kiel played "all" of the Kanamits in the episode. He didn't speak any dialogue because he had just finished working on another project and didn't have the time to learn his lines. Another actor did the voiceover. It worked just fine.
Moore in his 2009 memoir My Word Is My Bond described how Kiel was starkly different from his Jaws character.
'Richard is so kind, so gentle,' Moore wrote of his co-star.
Kiel's abnormal height and distinct features were a result of a hormonal condition called acromegaly that is often associated with gigantism.
Kiel published an autobiography in 2002 titled Making It Big in the Movies.
He also co-authored the 2007 book Kentucky Lion: The True Story of Cassius Clay about the politician who worked for the abolition of slavery.