In the middle of the Argentine jungle, in the province of Salta, a biologist named Dante and a photographer named Martín seek to photograph the elusive Andean bear, the only Upside in South America, accompanied by Silvestre, a Wichi guide (ethnic group belonging to the Argentinean north).
At nightfall and in the light of a fire, the guide tells Dante and Martín five stories about real sightings of a humanoid monster half bear half man, known as the Ucumar, which terrorized the locals several years ago. Between story and story, and before Marti´s naivety, Dante will try to convince Silvestre that the Monster is simply an Andean bear, based on scientific data. But Silvestre is not a man of science…