Claim: The Mysterious Island published by Hetzel in 1875 is a crossover sequel to Verne's famous Twenty Thousand Leagues Under the Seas and In Search of the Castaways but initially rejected by Verne's publisher.
Evidence: The Mysterious Island (French: L'Île mystérieuse) is a novel by Jules Verne, published in 1875. The novel is a crossover sequel to Verne's famous Twenty Thousand Leagues Under the Seas (1870) and In Search of the Castaways (1867–68), though its themes are vastly different from those books. An early draft of the novel, initially rejected by Verne's publisher and wholly reconceived before publication, was titled Shipwrecked Family: Marooned with Uncle Robinson, seen as indicating the influence of the novels Robinson Crusoe and The Swiss Family Robinson.