I recently saw this film from way back in 1990. It has an incredibly good Maurice Jarre score but that is only matched by the sheer excellence of the film itself.

Roger Ebert review from 2005:

After Dark, My Sweet is the movie that eluded audiences; it grossed less than $3 million, has been almost forgotten, and remains one of the purest and most uncompromising of modern films noir. It captures above all the lonely, exhausted lives of its characters.