Biography: Betty Luster (April 27, 1922 — May 25, 2011) was an American television actress, singer, and dancer, whose career was active in the 1940s and 1950s. The role for which she is best remembered today was at one time her most obscure: her portrayal of Mr. B Natural in the short film of the same name, made famous after its inclusion in a 1991 episode of Mystery Science Theater 3000.