For Men Only, and with Loan Shark, also released in 1952 and starring George Raft. His early roles were primarily in Westerns such as Rancho Notorious (1952, starring Marlene Dietrich), Seminole (1953), Law and Order (1953, opposite Ronald Reagan), and Badman's Country (1958), and science fiction films such as It Came from Outer Space (1953), This Island Earth (1955), Attack of the Crab Monsters (1956), and The Space Children (1958). He also appeared in a Ma and Pa Kettle vehicle, Ma and Pa Kettle at Waikiki (1955), as well as in Roger Corman's rock-'n'-roll crime drama Rock All Night (1957). In 1955, he had a role in Many Rivers to Cross along with Alan Hale Jr., later the Skipper from Gilligan's Island. Johnson and Hale also appeared together in an episode of the TV series, Casey Jones Season 1 Episode 20 "The Track Walker". During the 1950s, he played the head of a gang of crooks in episode 17 of season one of The Adventures of Superman (originally broadcast in January 1953, filmed in 1951). Johnson was also cast on the religion anthology series Crossroads. In 1957 he played a ruthless and heartless murdering outlaw named "Stranger" (so out of character from his future "Professor" role) on the TV Western Gunsmoke in the episode "Bloody Hands" (S2E21), where he almost convinces Matt Dillon to quit from guilt because of his own constant need to kill. He returned to that series in 1959 as “Harry Webb” in the episode “The Bear”. He also played the Sundown Kid in an episode of the 1958 NBC's Western series Jefferson Drum and guest-starred in another NBC Western series, The Californians. He appeared in episodes of Wagon Train, "The Beauty Jamison Story" and "The Cliff Grundy Story." He appeared four times on the first-run syndicated military drama The Silent Service, based on actual stories of the submarine section of the United States Navy. He was cast as Hugh Grafton in episode 28, "The Gar Story", as the executive officer Beach in the 1957 "Tirante Plays a Hunch", appeared twice as submarine officer and later author Edward L. Beach Jr., and as Tom Richards in two 1960 episodes, "Intermission" and "The Desperate Challenge", and twice with June Allyson on her CBS anthology series The DuPont Show with June Allyson. Also, he guest-starred with William Shatner in "The Hungry Glass", a 1961 episode of Thriller, and with