It is the 17th century in Cartagena of the Indies (modern day Columbia), a time and place in which the slave trade is alive and well.  Thirteen year old Calepino, orphaned by his mother who died on a slave ship, finds himself in comfortable circumstances.  The  noblewoman Dona Isabel has taken him in and shown an interest in his education.  Through his studies, Calepino shows an affinity for languages and soon is fluent in 11 of them, both African and European.   This talent serves him well when, on his 13 birthday, he is taken in by the local Catholic priest Father Pedro to work in the monastery.

Father Pedro introduces Calepino to a cruel world that he only narrowly escaped.  They board crowded and stinking slave ships to care for the sick and dying.  They visit slave holding cells to administer last rights.  Through their work together, Calepino meets Mara and Tomi, a mother and son slave who have recently been brought over and are now working for a cruel master.  Mara and Tomi remind Calepino of his own past and he feels obligated to help them.

Calepino creates a plan to free Mara and Tomi and allow them to escape to the palenques, a hidden settlement of escaped slaves.  To do this he must reach out to his friend Dr. Lopez who treats patients at the local leper colony.  But Dr. Lopez has his own problems when he is hauled before the inquisition courts on charges of practicing his Jewish religion.  Through all of this, Calepino will learn how dangerous it is to help others in a time of great cruelty.

This is a wonderful juvenile historical fiction novel for anyone interested in the slave trade, 17th century South America, or early Columbia history.  Ages 9-11.