He attended Francis Scott Key High School before moving on to the University of South Florida on a swimming scholarship, where he earned a BFA in music composition in 1979.

Guy performed and recorded with several artists such as Mike Pinera, Iron Butterfly, Blues Image, Luis Cardenas and Renegade.

In 2001, Babylon won a Grammy Award for his contributions on the Elton John / Tim Rice musical Aida.

Babylon also worked extensively on the Elton John / Bernie Taupin musical Lestat, (based on the Anne Rice novels).

Until his death, he lived in Los Angeles with his wife and children, and was a member of Elton John's six-member touring and recording band.