A longtime resident of Maple Shade Township, New Jersey, Muldowney studied ballet as a child, and began performing interpretive dances of fictional characters in 1976. By 1980, she was appearing at costume contests at science fiction conventions. It was during this time that Muldowney started performing as the cartoon superhero Underdog. She has explained in an interview, "I try to do certain movements that simulate flight and heroism. I'll make like I'm flying by doing leaps and other things. I also will do some camel spins. Basically I do movements that best portray Underdog. I try to do him more refined and sophisticated than the original character was."
In 1987, Muldowney began appearing in seasonal parades up and down the East Coast. Though her most famous dance interpretation is of Underdog, she has also portrayed Dracula, Catwoman and Supergirl, along with self-created characters such as Shelley the South Jersey Shore Mermaid, Irish Cinderella, and Spectrum the Ghost King. She sews all her own costumes, which are known for their exacting detail and elaborate ornamentation. For example, the interior of her Underdog cape is lined with streaks of silver, representing the streaks of light trailing behind the animated Underdog.
Muldowney made several appearances on Howard Stern's radio and television shows throughout the 1990s. A serious performer, she regrets her association with the program because of Stern's lewd jokes, and has called him her "nemesis". In 2006 she appeared as a guest on Jimmy Kimmel Live! to demonstrate a new form of dancing she called "figure jogging".
In 2006 the documentary My Life as an Underdog was released by director Boris Gavrilovic.
- Staff. "Underdog gives woman new leash on life", Courier-Post, April 17, 1999. Accessed February 4, 2013. "Muldowney has spent more than a quarter century interpreting the cartoon canine hero in parades and conventions, even onstage at New York University.... A native of Maple Shade, she calls herself an improvisational or interpretive dancer."
- William H. Sokolic. "Underdog gives woman new leash on life". Courier Post. April 17, 1999. 2B.
- Bob Cooney. "Big fat close-up". Philadelphia Daily News. October 1, 1999. 60.
- Bernard Harris. "30th Loyalty Celebration features 115-unit parade and 4-day carnival". Lancaster New Era. April 24, 1998. d16.
- Rob Laymon. "Performance artist saves day for Underdog". The Press of Atlantic City. May 2, 1994. C1.
- Dave Caldwell. "Is It Summer Yet? Just Ask a Hermit Crab". New York Times. May 13, 2007. 7.
- "'My Life as Underdog' documentary Saturday". The Press of Atlantic City. November 1, 2006. C3.
- Scott Semet. "Area resident gets her time in the limelight in 'My Life'". The Press of Atlantic City. November 2, 2006. 34.
- Super Heroes to Unite at 2006 NJ State Film Festival! New Jersey State Film Festival. Retrieved on April 7, 2009.
- Suzanne Muldowney at the Internet Movie Database
- My Life as an Underdog at the Internet Movie Database
- Baltimore City Paper article[dead link]