Dragons have been seen in the mists behind Christ de Reginero. Simon's Aunt Leonis accepts an invitation for Simon to travel by freighter to Venezuela with Simon's cousin, Forsyth Phair. Phair recently purchased a valuable heirloom painting of Simon Bolivar from Aunt Leonis. It is a relic of Simon's forebear, Quentin Phair, who fought at Bolivar's side. The portrait was sold to raise money to support Simon and Miss Leonis, who is ninety years old. Forsyth proposes to donate the portrait to a museum in Caracas— but all is not as it seems. A dangerous "accident" involving a forklift and odd interactions aboard the Orion lead fellow passengers Poly and Charles O'Keefe to believe that Simon's "Cousin Forsyth" may be a source of danger to Simon. When Forsyth is murdered and the portrait stolen, Poly does not know what to think, but it is clear that Simon is still in danger.
Another passenger, Mr. Theo, calls for Poly's godfather, Canon Tallis, to come and investigate, but Tallis and Simon are both kidnapped by the local police chief upon arrival in Port of Dragons, Venezuela, and left stranded in the jungle. Miss Leonis also arrives, having learned before the murder that the check paying for the portrait was worthless. She has also just read Quentin Phair's letters and journals, thus learning belatedly that Simon's heroic ancestor left behind a wife and son among the Quiztano Indians of Dragonlake in Venezuela. Phair also started the "Caring Places", two large buildings in which Quiztano healers, some of them with medical degrees, help the sick and the dying. The connection between Quentin Phair and Umara of the Quiztanos is the underlying cause of Simon's current predicament, part of a tangled web of murder, smuggling, blackmail and a generations-old grudge. Alejandro Hurtado, a friend of Tallis, initially arrests Jan, a Dutch sailor with Quiztano blood, but the ship's first mate, Lyolf Boon, soon confesses to Phair's murder.
Simon and Tallis fight off an attack from a wild boar, but Tallis receives a leg injury, which becomes infected. When a wildcat attacks, Tallis orders Simon to run away. Panicked, Simon does so, but feels guilty afterward. Both are rescued by the Quiztanos and brought to Dragonlake. Miss Leonis is already there, and is dying. The Quiztanos hail Simon's arrival as the long-awaited "return of the Phair". After some initial resistance, Simon decides to stay at Dragonlake and continue the good work that his ancestor started with the Caring Places.