Mario and Carlo Grieco, heterozygous twins, were abandoned by their mother after their birth on 9 January 1963 at the Bari Polyclinic. They lived for 13 years a few kilometers apart in two towns in the province of Bari, convinced they had no siblings and without knowing they were adopted.
Then fate made them meet on board a bus while going to the same school they both attended without knowing each other. Mario is looking for her biological mother because he wants to meet her and ask her why she abandoned them.