Stephens, nicknamed the 'Fulton Flash' after her birthplace Fulton, Missouri, was a strong athlete in sprint events - she never lost a race in her entire career - but also in weight events like the shot put and discus throw, and she won national titles in both categories of events.
Aged only 18, Stephens was sent out to the 1936 Summer Olympics. There, she won the 100 m final, beating reigning champion and reigning world record holder Stanisława Walasiewicz of Poland (who an autopsy discovered was a man under present Olympic rules). Her time of 11.5 s was below the world record, but was not recognised because a strong backwind was present at the time of the race. Next, Stephens anchored the American 4 x 100 m relay team that won the Olympic title after the leading German team dropped its baton.
Stephens is quoted by Olympic historian David Wallechinsky about her post-race experience with Hitler. "He comes in and gives me the Nazi salute. I gave him a good, old-fashioned Missouri handshake," she said. "Once more Hitler goes for the jugular vein. He gets hold of my fanny and begins to squeeze and pinch, and hug me up. And he said: You're a true Aryan type. You should be running for Germany.' So after he gave me the once over and a full massage, he asked me if I'd like to spend the weekend in Berchtesgaden." Stephens, whom it later emerged was a closeted lesbian, refused.
Stephens retired from athletics shortly after the Games and played some professional baseball and softball. She attended William Woods University in Fulton, MO. From 1938 to 1952, she was the owner and manager of her own semi-professional basketball team.
She died in Saint Louis at age 75.