Prior to her acting career, Simone served in the United States Air Force as an engineering assistant. Afterwards, she sang background for various European artists and was part of Spanish artist Raphael's touring chorus.
Simone's stage debut was in a national tour of the Andrew Lloyd Webber rock musical Jesus Christ Superstar, as Soul Sister and understudy for Mary. In 1996, she continued her career as a swing and female understudy in the original Broadway production of Rent. Later that year, Simone performed the lead role of Mimi Marquez in its first national tour, from November 1996 to April 1998.
Starting in 1998 Simone took a hiatus from acting during which she toured and recorded two albums with acid jazz band Liquid Soul. Along with the rest of the band, she was nominated for a Grammy Award for their 2000 album Here's the Deal. Simone then returned to the Broadway stage in the Disney musical Aida as Aida. She performed the role from January 29, 2002 until June 15, 2003. She reprised this role for a short time at The Muny Theater in St. Louis in the summer of 2006. In the summer of 2007, she played the role of Fantine from Les Misérables at the Muny.
Simone has released two solo albums, Simone Superstar and Simone on Simone.
She tours frequently, singing jazz standards and her own material.
Simone is the daughter of Nina Simone and Andrew Stroud. She is married to Robert Kelly, with whom she has a daughter.