The Secret in the Attic (2005)

A beautiful woman marries a wealthy man, who for years chose to be a bachelor inspite of numerous female suitors. At first the marriage is perfect; he’s a loving husband and an enthusiastic lover. But soon the romance cools and the wife discovers that it has to do with a secret kept in the attic, something – or someone – he visits every night, that is changing him from a loving husband into a stranger… Akira Fukamachi directs this erotic and atmospheric drama.

Unfortunately the movie The Secret in the Attic is not yet available on HBO Max.