The Duke of Burgundy

Cynthia, a woman who studies butterflies and moths, shares a carefully ritualized life with her lover, Evelyn. Day after day, they perform an elaborate sadomasochistic fantasy of mistress and maid, built around domination and submission. But as the routine begins to lose its power, Cynthia longs for a more conventional intimacy, while Evelyn presses to take their taboos further.