'The American Guest' takes place at the beginning of the 20th century. After a bitter defeat in the American presidential campaign, Roosevelt sets off in search of his lost youth in the Brazilian jungle, alongside his longtime friend Farrel Nash (David Herman) and by son Kermit (Chris Mason), with the aim of exploring the last uncharted river in the country: Rio da Dúvida, the River of Doubt, in Rondônia.