Martin Mull is an American actor who has appeared in many television and film roles. He is also a comedian, painter, and recording artist. As an actor, he first became known in his role on Mary Hartman, Mary Hartman and its spin-off Fernwood 2 Night. Among his other notable roles are Colonel Mustard in the 1985 film Clue, Leon Carp on Roseanne, and Willard Kraft on Sabrina, the Teenage Witch.
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