Jeff was born in Brooklyn and attended Erasmus High School. After high school, he took a drama course and worked in stock companies for two years. His next role would be that of an officer in World War II. After he was discharged from the service, he became busy acting in radio drama's and comedies until he was signed by Universal. It would be in the fifties that Jeff would become a star making westerns and action pictures. He would be nominated for an Academy Award for his role as Cochise in Broken Arrow (1950). He would follow this by playing the role of Cochise in two sequels: The Battle at Apache Pass (1952) and Taza, Son of Cochise (1954). While his premature gray hair and tanned features served him well in his westerns and action pictures, the studio would put him into soaps and costume movies. In his films, his leading ladies would include Maureen O'Hara, Rhonda Fleming, Jane Russell, Joan Crawford, and June Allyson. Shortly after his last film Merrill's Marauders (1962), Jeff died, at 42, from blood poisoning after an operation for a slipped disc.