Homage to Hitchcock?
Or as Woody Allen would say, a direct steal?
Oh, possible spoilers.
The score and use of music in this movie was very Hitchcockian and in at least one scene the film-makers seemed to be making reference to him.
It's the scene where the lead actor has prepared a steak dinner for the dead woman's sister and she asks him if he has a sharper knife.
The sound focuses on the word 'knife', repeating it and getting louder and louder.
There is a Hitchcock film - can't be bothered looking it up but it's an early one - where the word 'knife' is used in precisely the same way.