Shock Treatment is a 1981 American musical comedy film directed by Jim Sharman, and co-written by Sharman and Richard O’Brien. It is a follow-up to the 1975 film The Rocky Horror Picture Show. While not an outright sequel, the film does feature characters from the previous film, most portrayed by different actors, as well as several Rocky Horror actors in new roles.
But, to be fair, RHPS is also awful (as a movie). I love the music, and the experience of seeing it in a theater is great, but the actual move is garbage.
I enjoy the soundtrack to Shock Treatment and still listen to it from time to time.