Stuntwoman and actress Mary Katherine Peters was born in California. The youngest daughter of a California policeman, Mary ran track and field in high school.

Peters began her career in the entertainment industry as a model for 20th Century Fox. Mary's big break as an actress happened after she was cast as an extra for five years on the hit TV series M*A*S*H (1972). Peters attended various professional schools to learn all about performing stunts whenever M*A*S*H (1972) was on its six month filming hiatus and began her career as a stuntwoman in 1976.