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Mark Ritts

Mark Ritts (born June 16, 1946 in West Chester, Pennsylvania, died December 7, 2009) was an American actor, television producer, and director prominently known for portraying the role of Lester the Lab Rat in the children's educational television series, The Best of Beakman's World.

Mark Ritts co-directed Barney's First Adventures alongside Jay Renfroe which originally aired as a primetime special on the Fox Kids network in 1998.