Hayes' initial contract was with
Warner Bros. Having little success there, she signed with
Paramount Pictures. Hayes was often billed as Maggie Hayes in her film credits. She is perhaps best known for her performance as schoolteacher Lois Judby Hammond in the 1955 film
Blackboard Jungle. In 1956, she guest-starred as
Dora Hand in three episodes of
The Life and Legend of Wyatt Earp. She appeared in the episode "The San Saba Incident" (October 18, 1957) of
Trackdown, playing a female convict, named Abby Lindon. Hayes' films included
The Glass Key, ''
Sullivan's Travels, and Good Day for a Hanging. In 1958, in the film Damn Citizen'', Hayes appeared opposite
Keith Andes in the role of a real person, Dorothy Maguire Grevemberg, the wife of the crusading
Louisiana State Police superintendent Francis Grevemberg. She made four guest appearances on CBS's
Perry Mason, including as defendant Sybil Granger in 1957 episode "The Case of the Nervous Accomplice". She co-starred on Tombstone Territory season 1 episode 24 'Cave-In' which aired March 26, 1958. In 1961, she portrayed Mrs. North in the episode "Incident of the Night on the Town" on CBS"s
Rawhide. In the same year, she also guest-starred in an episode of
Bonanza, "The Countess", as Lady Linda Chadwick. ==Journalism==