Duetto takes place in 1965 and tells the story of 18-year-old Cora, a Brazilian from an Italian family who, after losing her dad in a tragic car accident, goes with her grandmother Lucia to Puglia, Italy, where her ancestral homestead still stands. Lucia, aiming to sell an old family land lot, reencounters her sister Sofia and her husband Gino, whom she hasn't spoken to in 40 years.
Gabriele is a divorced dad who owns a music store and is completely focused on taking care of his 10-year-old daughter Sofia who spends time with both parents. One day he bumps into his old friend Mara who - for the first time since his separation - reignites his desire to be in a relationship. There is only one problem, Mara hates children!
Carlo is a doctor that has recently lost his wife. Affected by the loss, he is supported by his family and friends, and, above all, for the love he feels towards his little daughter. And then, one day, he meets Camille.