Emilia, 17, arrives at a hostel owned by her Aunt Inés at the border between Argentina and Brazil, looking for her long missing brother. In this luxuriant jungle, where local myths and legends abound, a dangerous beast believed to be the spirit of an evil man taking the form of different animals seems to be roaming around. On a journey to sexual awakening, Emilia will have to confront her past in order to kill the beast.