Alex Cold is the novel’s protagonist and the character whose perspective most colors the narrative. Alex starts out as an average fifteen-year-old from the California coast who “had never felt any great curiosity to explore beyond the safe boundaries of his own existence” (15). He lives with his two sisters, Andrea and Nicole, and his parents, John and Lisa. Alex is a skilled mountain climber and flutist and, until his mother gets sick, he leads a happy and uneventful life. When he learns that he’ll have to join his grandmother Kate on her trip to the Amazon, Alex is initially frightened and angry, but once the trip begins, he quickly becomes engaged in his exciting new surroundings and the complex issues surrounding the peoples and environment of the Amazon. Though narrow-minded and skeptical at first, Alex grows significantly more mature and capable over the course of the novel. Aided in large part by his new friend Nadia Santos, Alex learns to appreciate the metaphysical mysteries of the native people and loses his attachment to the strictly rational mindset he once relied on. 

Alex is somewhat passive at the start of his journey, merely observing and learning from those around him, until he glimpses his true nature through his encounter with the black jaguar at Mauro Carías’s compound.