Born in Susanville, California on September 8, 1915, Cady studied journalism at Stanford University and met his future wife Shirley there. Following graduation, Cady served an apprenticeship at the Westminster Theater in London, appeared in four plays, and made an appearance on television on the BBC in 1938. He returned to Stanford but was unhappy as a teaching assistant so went into broadcasting.
He appeared in several movies, like Rear Window and When Worlds Collide, but became best know for his work in television. Cady had a recurring role as Doc Williams on The Adventures