Three Brothers Plus One is about a baby girl who was kidnaped by the Italian Mafia in Naples, Italy, and held for ransom. The ransom was paid but, when they demanded more, the second demand was met. The little girl was brought to the United States to New York City in a section in lower Manhattan where she was to be trained as a prostitute to work in a brothel by a branch of the New York City Mafia. While walking through Greenwich Village Park in New York City on the way home from a late night at the opera, three brothers and a close friend find a small bundle on a park bench. They had discovered this abandoned baby girl wrapped up in it. The single working mother of the three boys attempts to locate her family. Because of the political upheaval going on in Italy at the time, she could not locate the child's family or her find out her origins. She finally legally adopts her. Years later, one of her three sons (now the girl's adult, adoptive brother) attempts to find the baby girl's family and roots.
