Private Vices, Public Virtues (1976)

"Royal passions that rocked a Crown..."

The setting is a Central European kingdom, near the turn of the century. Bored by his very proper wife, the youthful heir to the throne spends his time in amorous dalliances at a sprawling country estate. His wife departs at the arrival of his friends, and they organize a celebration which becomes a wild orgy and culminates in death and tragedy.