ohn Garman "J.G." Hertzler (born 18 March 1949; age 64) is an American actor from Savannah, Georgia, who has portrayed many different roles on several Star Trek series. He is one of only five actors to play seven or more different characters in the Star Trek franchise, the others being Jeffrey Combs, Randy Oglesby, Vaughn Armstrong and Thomas Kopache. Hertzler's best-known role is Martok, whom he played for four seasons on Star Trek: Deep Space Nine. He also wrote the continuation of his character's story in The Left Hand of Destiny novel diptych with Jeffrey Lang