Adrián is a boy who has been admitted to hospital. His stay there will soon become a unique experience: to his surprise, he is selected to form part of a special group of superheroes and becomes Eagle Boy. Along with his new superhero friends he will confront villains such as Lady Sad and Gloom. These baddies try to fill society with sadness, despondency and distress, but Eagle Boy and his friends won't make things easy for them. Adrián and his fellow adventurers will use their days in hospital as an opportunity to find true friendship, understand how people really feel and put an end to all the negative things that sometimes slip into human thought.