Avanti! is a 1972 romantic comedy film directed by Billy Wilder. The film stars Jack Lemmon and Juliet Mills, and it is based on the play "Cactus Flower" by Abe Burrows. The story follows the character of Wendell Armbruster Jr. (Lemmon), a wealthy American businessman who goes to Italy to retrieve the body of his deceased father who had died in a car accident.
When Armbruster arrives in Italy, he discovers that his father had been spending time with a mistress named Pamela Piggott (Mills) and had died with her in the car crash. Armbruster is shocked and upset by the news and tries to deny the reality of his father's infidelity. However, despite his initial reluctance, Armbruster eventually starts to develop feelings for Pamela and they begin a romantic relationship.
The rest of the film follows the couple as they try to navigate their complicated relationship while dealing with the cultural differences and language barriers between them. Along the way, they encounter several quirky characters, including an eccentric hotel manager and an Italian lawyer who helps them unravel the legal complications surrounding the inheritance of Armbruster's father's estate.
The film is well-known for its humorous depiction of the clash between American and Italian cultures and its exploration of themes such as love, infidelity, and the complexities of family relationships. It was a critical and commercial success upon its release and is considered one of Wilder's most underrated films.