The Lighthouse Fire is a sequel to the Lighthouse Library and is another adventure of ten-year-old Rocky Linfield. It was October of 1952 when ten-year-old Millie Harris moved in with the Linfield family, who ran the lighthouse in Crafton, Maine. Millie's stay was to be temporary while her parents delivered a yacht to the Bahamas. Millie was told by an FBI agent, her half-sister, that her parents had been kidnapped, but no ransom demands had been made. A second yacht with CIA agents aboard was being sent to the Bahamas to investigate. Millie felt it was her duty to help, but she could not do it alone. She recruited Rocky to join her, and they became stowaways on the yacht. When they got to the islands, the youngsters discovered the reason for the kidnapping and received help from Pinky, a native Bahamian who worked for the United States Navy during World War II by watching for Nazi submarines. Suffering attacks with a grenade, flares, a scouting knife, and Rocky's slingshot, the kidnappers paid for their crimes.