On the Threshold is a postmodern and futuristic novel. The story is based in the hinterland of Brazil, specifically in the Araguaia and Xingu region in the state of Mato Grosso, involving indigenous ethnicities in conflict with agribusiness and glimpsing the mysteries of the Roncador mountain range. It envisions how this reality will be transformed by the transoceanic railroad, the manned drones that will appear in the near future, altering the new agroecological and anthropological trends in the region, as well as different ways of life that will appear by 2028. The main characters are the indians Obajara and Kunhahendy, undercover federal intelligence agents who clash with the organized crime that migrated to the region at the beginning of the 21st century. They also show a new form of relationship, both erotically and socially, proposing a new pact of pleasure and conviviality, breaking with the decadence of traditional monogamy.