Some Like It Cool (1977)

While hiding from the royal authorities, Giacomo Casanova, the famous romancer, encounters his look-alike: Giacomino, a fugitive petty con man. Meanwhile, the Arabian Caliph and his wife are arriving in Venice for a state visit, and she insists on a night with the legendary lover. Through a series of erotic encounters and mistaken-identity comedies, Giacomo and Giacomino make their way back to Venice for their appointment with the Caliph's wife.