The Dreamer opens on Neftalí Reyes, a young boy in Temuco, Chile, recovering from a recent illness and forced to stay in bed by his father, José, who sees Neftalí as a “weakling.” He orders Neftalí’s stepmother, Mamadre, to keep Neftalí in bed, hoping it will make him stronger. Mamadre heeds this directive, though it pains Neftalí, but she is otherwise kind and supportive toward her stepson. Neftalí has an older brother named Rodolfo and a younger sister named Laurita. Uncle Orlando, Mamadre’s brother, lives nearby.

Though his father yells at him for it, Neftalí can’t stop daydreaming, bringing his idle surroundings to life with his active imagination. A wave of rainwater sweeps into his room and carries him to the ocean, where he captains a ship traveling to far-away places. Slips of paper on which he’s written words he likes float out of their drawer and arrange themselves in shapes and patterns in midair. Father tells Neftalí his mother was the same way, and Neftalí wonders if daydreaming made her so weak that she died. Mamadre tells him the truth: His mother died from a fever when Neftalí was a baby, not from daydreaming.