Jacques Joseph O'Mahoney, known professionally as Jock Mahoney, was an American actor and stuntman. He starred in two Western television series, The Range Rider and Yancy Derringer. He played Tarzan in two feature films and was associated in various capacities with several other Tarzan productions. He was sometimes credited as Jack O'Mahoney or Jock O'Mahoney. Jock entered the University of Iowa in Iowa City and excelled at swimming and diving, but dropped out to enlist in the United States Mar...