Flannery was born in Jersey City, New Jersey, on July 31, 1939, and attended school in Manhattan. She received her BA degree from Stephens College, a women's college in Columbia, Missouri, in 1962.
Flannery is known for playing Dr. Laura Spencer Horton from 1966 until 1975 on Days of Our Lives, where she met writer and daytime legend William J. Bell (who would later cast her in the daytime soap he would create called The Bold and the Beautiful in 1987). She acted in feature films, including The Towering Inferno (1974) and The Gumball Rally (1976). She also acted in the primetime television series Dallas, playing Leslie Stewart during season four (1980–1981), and appeared in an ensemble cast with Kirk Douglas and Christopher Plummer in the 1976 NBC miniseries The Moneychangers.
Flannery became best known worldwide for portraying Stephanie Douglas Forrester on the American soap opera The Bold and the Beautiful (1987-2012). She was one of the original cast members of the series, only two of whom still appear (Katherine Kelly Lang and John McCook). Flannery was also a regular director on the show, and was twice nominated for a Directors Guild of America Award for her work. After 25 years, she decided to leave the show in 2012. In her final storyline, Stephanie Forrester lost her battle with lung cancer and died.
Flannery also appeared as a special guest on Good News Week. She appeared in a special episode of Wheel of Fortune with Deidre Hall (Marlena, Days of Our Lives) and Peter Bergman (Jack, The Young and the Restless) in 2006. Flannery also directed the October 13, 2008, episode of Guiding Light.
Flannery came in at #1 in the Top 50 Soap Actresses of All Time poll on the internet blog We Love Soaps in 2010.
She has taken an active role in the American Federation of Television and Radio Artists (AFTRA) in securing cable rights and foreign residuals for actors when their work appears in other media. Her efforts have had a positive impact on how The Bold and the Beautiful actors are paid when the show is televised in countries outside the United States.
Flannery has an adopted daughter, Blaise.
Gay rights activist Rita Mae Brown socialized with Flannery in Los Angeles in the mid-1970s. They met through their mutual friend Fannie Flagg. Brown wrote the following about Flannery in her 1996 memoir Rita Will.:
She'd been a star in a long-running TV program and had left to take a prominent role in a film. Almost white-blonde, with a heart-shaped face, blue eyes and a great figure, she appeared every inch a woman ready to become a major movie star. She had looks, talent and drive. What she lacked was the ability to kiss ass. Just when her career should have rocketed, it began to drop to Earth. Approaching forty added to the tension.
She is a fundamentally honest person, a decent one.
Word got about [directors and screenwriters] that she was difficult. That was amended to "difficult dyke." It wasn't too long before she languished in her beautiful shared Montecito, California home wondering what the hell had happened.
Were Susan at the same career fulcrum today [in 1996], she'd have a fifty-fifty chance of swinging up. In the mid-seventies, she had no chance. Today she's back on television [in supporting roles and character parts].
Because she didn't marry to play the game, she might as well have announced that she was gay. Other people announced it for her. She kept silent but stiff-armed any attempts to create a bogus heterosexual life. She and Fannie [Flagg] had been together for eight years. The cracks in their relationship widened under the pressure. Many of Susan and Fannie's friends knew they were lovers, but many didn't. The isolation, under the circumstances, had to have been extremely painful for Susan.
My heart went out to her. After my initial visit [to their Montecito home], the three of us palled around together. The more I knew Susan, the more I liked her.If there had been a way for the three of us to live together, I would have tried it because I grew to respect Susan and to value her for the generous and kind person she is. Like her Irish forebears, she engaged her crisis with good humor and the hope that she'd learn something.
|1965||Guns of Diablo||Molly|
|1967||The Gnome-Mobile||Airline Stewardess|
|1974||The Towering Inferno||Lorrie||Golden Globe Award for New Star of the Year - Actress|
|1976||The Moneychangers||Margot Bracken||TV miniseries|
|1976||The Gumball Rally||Alice|
|1978||Anatomy of a Seduction||Maggie Kane||TV movie|
|1979||Women in White||Dr. Rebecca Dalton||TV miniseries|
|1982||Money on the Side||Karen Gordon||TV movie|
|1983||Shaft of Love||Dr. Rose||TV movie|
|1963||Burke's Law||Lily's Secretary||Episode: "Who Killed Harris Crown?"|
|1964||Slattery's People||Nancy Rossman||Episode: "Question: What Are You Doing Out There, Waldo?"|
|1964||Voyage to the Bottom of the Sea||Katie/The Sister||3 episodes|
|1965||Death Valley Days||Jenny Hardy||Episode: "Birthright"|
|1965||Ben Casey||Elinor Cabot||Episode: "A Nightingale Named Nathan"|
|1966-1975||Days of Our Lives||Laura Spencer Horton||Contract role
Daytime Emmy Award for Outstanding Lead Actress in a Drama Series (1975)
|1966||Felony Squad||Stewardess||Episode: "The Immaculate Killer"|
|1966||The Time Tunnel||Louise Neal||Episode: "The Day the Sky Fell In"|
|1966||The Green Hornet||Janet Prescott||Episode: "Trouble for Prince Charming"|
|1981||Dallas||Leslie Stewart||11 episodes|
|1987-2018||The Bold and the Beautiful||Stephanie Forrester||Contract role
Daytime Emmy Award for Outstanding Lead Actress in a Drama Series (2000, 2002-2003)
|1993||The Young and the Restless||Stephanie Forrester||1 episode|
|2004||Hope & Faith||Laura Levisetti||2 episodes|