Gary Lockwood (born John Gary Yurosek;[1][2][3] February 21, 1937) is an American actor.[4]　　He is known for his roles as astronaut Frank Poole in the film 2001: A Space Odyssey (1968),[5] and as Lieutenant Commander Gary Mitchell in the Star Trek pilot episode"Where No Man Has Gone Before" (1966). He played numerous guest television roles from the early 1960s into the mid 1990s, a regular supporting role in Follow the Sun (1961–1962), and the title role of The Lieutenant (1963–1964).