Veteran American character actor (1901–1983) who played Dr Mark Piper, the Enterprise's chief medical officer, in the second Star Trek pilot, Where No Man Has Gone Before.
Paul Fix was an American actor, born in 1901, who appeared in hundreds of films and television episodes. He worked repeatedly alongside John Wayne and was best known on television as Marshal Micah Torrance in The Rifleman.
In Where No Man Has Gone Before he played Dr Mark Piper, the ship's surgeon during Kirk's first recorded mission as captain. Piper introduces the psychiatrist Dr Elizabeth Dehner to the bridge crew and later treats Gary Mitchell and Kirk on Delta Vega as Mitchell's powers grow.
The part was a single appearance: when the series went into production the producers cast DeForest Kelley as Dr Leonard McCoy. Fix continued working into the early 1980s and died in 1983.