- Charles Cooper: He is a 17-year-old teenager who lives with his family in Cambridge. He is the protagonist of the story and is described as curious and adventurous. After discovering a map in a box, Charles sets out on a quest to find the lost ship "Royal Merchant" in the hope of finding the gold it carries.
- Charles' Father: He is not given a name in the story, but he plays an important role in the discovery of the map and the subsequent search for the lost ship. He accompanies Charles on his journey and helps him along the way.
- The Slave: Although not a character who appears in person, the slave who owned the map is an important figure in the story. The map he left behind leads Charles and his father on their journey to find the "Royal Merchant."