A Passion (2001)

A young couple, Janna Marks (Stephanie Beaton, a feisty red-head) and Matt (Robert Knowlton) are invited to a strange house where everyone seems to be a bit too horny and sex-a-plenty is going on in every room. They figure, "When in Rome....." and join in on the fun. As the visits pile up and the months go by, they're invited to talk to the owner. He explains to them a complicated setup--they've been invited to be part of a secret network of "super-lovers" from around the world who provide "sexual entertainment" for high-paying customers, via participation or on a extremely secure television network.