Creator Sheldon Leonard mentioned in an interview that Henry was a good actress who was easy to work with. A casting director brought her in to audition and to meet him. Sheldon tested her and based on the screen test she got the part of Mrs. Bellows. She was first cast on the show January 22, 1966 in season 1 episode 18 in a one episode role playing a different character called “Myrt” (from the original black-and-white episodes). Her first appearance as Mrs. Bellows wasn’t seen until December 12, 1966 in season 2 episode 14, when she was introduced to Tony and Roger by Dr. Bellows for the first time. Originally, Emmaline Henry never intended to become an actress, for she had wanted to become a singer. By her teens she was appearing on local radio. She went to Hollywood in the early 1950s and found her way into the choruses of several musicals. Producers began noticing, however, that her comedy skills were superior to her singing. She toured in shows like Top Banana, and acted in the film of that show. She also succeeded Carol Channing in the play Gentlemen Prefer Blondes. Emmaline Henry made her television debut in a 1955 episode of the ZIV production, I Led Three Lives. This was followed by appearances in another ZIV TV show, Highway Patrol. She appeared on The Red Skelton Show in 1961 and, subsequently, did guest spots on various sitcoms, including ABCs The Farmer’s Daughter, The Munsters and Petticoat Junction. Her first starring role was as John Astin’s wife in the sitcom I’m Dickens, He’s Fenster, which also starred Marty Ingels in a series about a pair of zany carpenters. She appeared as Mickey Rooney’s wife, Nora Grady, in the short-lived ABC sitcom Mickey in 1964–1965. She made film appearances in Divorce American Style, Rosemary’s Baby, and Harrad Summer.

Following the cancellation of I Dream of Jeannie in 1970, Emmaline Henry made appearances on other sitcoms, including the anthology series Love, American Style, and in the dramatic television mini-series Backstairs at the White House. She was reportedly scheduled to become a semi-regular cast member on Three’s Company after she had guest-starred in a couple of episodes in the role of Chrissy’s boss, J.C. Braddock. Her final television appearance was on a wedding episode of Eight Is Enough, in an episode entitled “I Do, I Do, I Do, I Do”, which aired just a few weeks prior to her death. She enjoyed playing Mrs. Amanda Bellows and mentioned that people would often ask her where her husband, Dr. Bellows (Hayden Rorke) was. Although she often played wives, in real life she never married (nor did Rorke). Emmaline Henry died of brain cancer on October 8, 1979, aged 50. She was interred at Holy Cross Cemetery in Culver City, California.