During a sea voyage off the coast of Scotland—made on his yacht “Duncan” by Lord Edward Glenarvan with his family—an unusual, for these waters, hammerhead shark was caught. Inside it was found a bottle containing a damaged written document. From the surviving part of the note it becomes clear that Captain Grant is asking for help—an intrepid Scot and a famous captain. The official authorities of Great Britain refuse to assist in the search: the note was written two years ago, and the shipwreck location is unknown—only the indication of the 37th parallel remains… Then Lord Glenarvan himself sets out to search for Captain Grant—with his family, the children of Captain Grant, and, by chance, the geographer Jacques Paganel joining them.