Piano Concerto Macabre
For me, the music is one of the best things about this movie. It's, as one film music historian observed about other film scores, "post-Rachmaninoff shmaltz".
It's especially, uh, effective during Barry Warren's, as Karl Ravena, over-the-top recital. (This character is mercilessly parodied in Roman Polanski's Dance of the Vampires.)
As derivative shmaltz goes, this is one of the best.