Arrigo, a nine-year-old boy living in 18th Century Naples, spends most of his time on the streets singing for the coins he can get from tourists or swiping food from the street vendors. His one good friend is a monk, Fra Andreas, who over the three years they've known one another has taught Arrigo to read and write. One day after Fra Andreas announces to him that he must go to Rome, Arrigo meets a man, Bruno Croce, who after hearing the boy sing, decides he will make him a singing star. And in the process make a great deal of money for Bruno.

It doesn't take much for Bruno to convince Arrigo's poor parents to let him go to Rome with Bruno. Arrigo is of the impression that he will go to Rome and take singing lessons. He is not told that he will also be castrated.

On the way to Rome, they meet other travelers: a young English tourist named Richard Sackett and a legendary brigand, Giamberelli. Both like Arrigo's spirit and independence and find him charming.

When Arrigo and Bruno get to Rome, Arrigo's mission is to locate Fra Andreas to renew their friendship. Already the little boy is having second thoughts about joining in with Bruno's plans and he is wise enough to know he needs someone on his side in case Bruno turns out villainous. He does in fact find Fra Andreas, and he also finds out about Bruno's plans for him and what the impending surgery will be like.

Arrigo has not been a street urchin all his life without knowing a few tricks of his own. After some desperate and harrowing episodes, he manages to escape and return to Naples. However, the poverty and apathy of his family haven't diminished at all, so he decides to seek his fortune with Giamberelli's gang. The rest of Arrigo's story will be told in two future novels.