A group of rich Italians head out on a yachting trip to a deserted volcanic island in the Mediterranean. When they are about to leave the island, they find that Anna is missing. Anna's boyfriend Sandro (Gabriele Ferzetti) and her best friend Claudia (Monica Vitti) try unsuccessfully to find her.
While they are searching, Claudia and Sandro develop an attraction for each other. When they get back to land, they continue the search with no success. Sandro and Claudia proceed to become lovers and all but forget about the missing Anna. A search without a conclusion, a disappearance without a solution.
‘L'Avventura’ created a stir in 1960, when Pauline Kael picked it as the best film of the year. "Too shallow to be truly lonely," Kael wrote, "they are people trying to escape their boredom by reaching out to one another and finding only boredom once again." For Martin Scorsese “this film gave me one of the most profound shocks of my life.”
At its premiere at the 1960 Cannes Film Festival, it was booed so much to the extent that Michelangelo Antonioni and Monica Vitti fled the theatre. However, after the second screening there was a complete turnaround in how it was perceived, and it was awarded the Special Jury Prize, going on to become a landmark of European cinema.