Stasera mi butto (1967)

The son of an Italian Countess meets a young lady staying at a seaside resort with friends. His attentions are turned when a U.S. celebrity, Lola Falana, comes to town and steals his affections. Marisa, the young lady, thinks she should turn her attention to a professor also staying at the resort, but her friends think otherwise and push her to fight for her young man.