Celeste is a poor girl living with her mother Lucia. Lucia has cancer, and although she tries to hide it from Celeste, Celeste discovers it. Celeste works in a plant nursery, and one day, while transferring plants, she meets Franco, whose car is stuck and he needs help. She helps him and he invites her to coffee. As they talk Franco tells Celeste the legend about the sun and moon (In Spanish Sol y Luna): St. Franciscus once gave all he had to `Brothers sun and Sisters moon`; he thought that names have no importance and therefore he called the men Sol and the women Luna. After telling her the legend, Franco asks her name and she answers: Luna. Without knowing each other`s true names, they set to meet in the same place the next day. Meanwhile, Lucia gets worse and is dying. Franco and Celeste continue to meet and they plant a tree together. They swear that as long as it lives, they will love each other. They set to meet the next day and tell their real names.