In 1874, Lady Clarissa Egerton, a twenty-three-year-old British marchioness, sails across the Solimões River aboard a luxurious steamship accompanying her husband Richard as he sets up operations of a new gold rush—the rubber trade. During their trip, Clarissa meets one of Richard’s childhood friends, Maurice, and instantly falls in love with him. Together, the trio play dangerous games of love and seduction as they explore their sexuality and the new world of the Amazon until tragedy strikes.

In 1974, Gabby da Silva, a twenty-three-year-old, freshly-graduated Brazilian doctor, returns home—a small village in the delta of the Solimões River—for one last Christmas break before cutting ties with her toxic extended family. She saves Moacyr, a gringo who narrowly survived a brutal attack by river pirates that left the entire crew and passengers of the cruise ship dead. Together, Gabby and Moacyr work to bring justice to the victims and to solve the mystery of his lost heritage. Their bond quickly blossoms into a once-in-a-lifetime ardent love until they fall victims to envy and jealousy.

When in 1874, Clarissa’s actions to protect herself and the ones she loved changed the course of history, a hundred years later, Gabby suffers every day the ripple effects of Clarissa’s actions. Even more, as Moacyr faces wrongful accusations of being the Boto Rosa—a mythical shape-shifter who seduces and impregnates women. While the locals conspire to seek revenge against Moacyr/the Boto Rosa, Gabby must decide between following Clarissa’s footsteps—and lying and killing—or breaking the cycle at the cost of her downfall.