This book is about a boy named Antonito who's family lived on a farm in Spain at the time of the Civil War
Antonito helped deliver a black bull and they become firm friends. He names him Paco.
He learns that his uncle is a bull fighter who tells him that Paco will one day be a fighting bull in the bullring, so the boy decides to set Paco free and run away. While setting his bull free, Antonito hears bombing in his village and returns home to find his family are all dead or missing. He then loses the bull as well.
Later he meets up with his sister, who'd missed the bombing as she had gone to look for Antonito.
He finds his uncle has become a fighter and a hero, and Antonito and his sister meet up with him.
He then learns that there is a legend of a black bull that chases away the baddies, and Antonito hopes that this is Paco.
The illustrations are perfect for the story. If I have one criticism it is that the book is too short, it took us only an hour to read.