Before they were famous Tom Gossin and Mike Gossin of the American country music group Gloriana appeared, uncredited, in the film during the "party scene" playing a song acoustically in an all-out jam session. The brothers recorded a song for the film from a 1930s tune that was in the public domain. Later in post-production the song was replaced, but the boys are still in the film jamming away.
The famous hallway jump scare in The Excorcist III was replicated in this but poorly executed.