Phantoms
From RockyWiki
In The Rocky Horror Show, Phantoms refers to the masked actors providing the backing vocals. In the original production there were three Phantoms. The Phantoms do not interact with the show in any way other than to provide the vocals and move set props between scenes. In some versions of the play, the Phantoms are played by the understudies. In The Rocky Horror Picture Show, the Phantoms were replaced by the Transylvanians, brightly dressed party goers from Transsexual, Transylvania invited to view the unveiling of Dr. Frank-N-Furter's Rocky Horror (A Creation).