On television, Mitchell's credits include acting in two episodes of Alfred Hitchcock Presents called "Wally the Beard" (original air date March 1, 1965) with co-stars Larry Blyden and Kathie Brown, in which he played a knowledgeable and cranky seller of boats, and "Forty Detectives Later" (airing April 24, 1960), in which he portrayed the client of a private detective (James Franciscus) whom he hires to track the supposed murderer (Jack Weston) of his wife.

George Mitchell acted in several films and television episodes with his wife, Katherine Squire, the two of them often playing a husband-and-wife couple intrinsic to the story.

[3] George Mitchell's major acting credits include the film The Andromeda Strain (1971), directed by Robert Wise, co-starring Arthur Hill, and based on the novel of the same name by Michael Crichton.

Another speciality was police/crime shows: Perry Mason, Peter Gunn, The Detectives Starring Robert Taylor, The Untouchables, Stoney Burke, Sam Benedict, and Naked City.

He even tried comedy (Hazel, The Ghost & Mrs. Muir, Bewitched), medical (Ben Casey), and science-fiction-adventure shows (Time Tunnel, Land of the Giants, and Voyage to the Bottom of the Sea).