Greta is thirteen years old and has to solve two big problems. The one she has with her schoolmates, who make fun of her because she is different and the even more serious one with food. She is so thin and weak that she risks getting sick, but is unable to eat as she would like. To make it, she knows she must find a strong motivation, something that stimulates her to overcome her limits and free herself from the monster that persecutes her and is destroying the planet. He is the one who spies on her day and night and makes fun of her. But why is she the only one to see it? In reality this is not entirely true: even plants and animals notice of his menacing presence. What is happening? By following their stories we will learn about the effects of the changes climate in a compelling crescendo of emotions and environmental awareness. Now that we can all see the monster, defeating it is up to each of us.