He is most recognized for his role as Link Larkin in John Waters's Hairspray (1988).
In 1989, St. Gerard starred in two movies in which he portrayed Elvis Presley: Heart of Dixie and Great Balls of Fire!.
[2] He also appeared in 1993 as Elvis's mirror image in the penultimate episode of Quantum Leap, titled "Memphis Melody."
He then made a few direct-to-video films, including Into the Sun (1992), Live Wire, and Replikator (1994)[3] In 1994, St. Gerard had a spiritual awakening after leading a Sunday School class, and after it, he decided to retire from acting at age 33 to focus on religious instruction.
He became a pastor in the Harlem area of New York City, extending himself and his church in particular to inner-city youths.