the title character, florencia grimaldi, is a famous opera soprano returning to her homeland to sing at the opera house in manaus with the hope that her performance will attract her lover cristóbal, a butterfly hunter who has disappeared into the jungle. she boards the steamboat "el dorado" for a trip down the amazon river, along with several passengers who are traveling to hear her sing. the passengers, however, are unaware of her identity. one of them, rosalba, is a journalist planning to write a book about grimaldi and hoping to interview her. in preparation, rosalba has compiled a notebook for two years with information about the diva.