Deep in the Brazilian Rio Negro, an enigmatic scientist is developing a drug that could alter the lives of women for ever. But Dr Annick Swenson’s work is shrouded in mystery - especially from her investors, whose patience is fast running out. When Anders Eckman, a mild-mannered lab researcher, is sent to investigate, a curt letter reporting his untimely death is all that returns.

Now Marina Singh, Anders’s colleague and once a student of the mighty Dr Swenson, is their last hope. Leaving the snowy plains of Minnesota, Marina retraces her friend’s perilous steps, determined to track down Dr Swenson and uncover the secrets being jealously guarded among the remotest tribes of the rainforest.

Little does she knows that, in this ancient cornee of the jungle, where the muddy waters and susurrating grasses hide countless unknown perils and temptations, she will face challenges beyond her wildest imagination. Marina is no longer the student, but only time will tell if she has learnt enough.