Vincent is one of New York's leading puppeteers and creator of the popular kid's television show Good Day Sunshine. But his world is turned upside down when his nine-year-old son Edgar goes missing on his way to school.

Struggling to cope with the situation, Vincent grows increasingly distressed and volatile. Full of guilt, he clings to his son's drawings of a blue monster puppet named Eric, convinced that if he can get Eric on TV, then Edgar will come home.

As Vincent's progressively destructive behavior alienates his family, his work colleagues, and the detectives trying to help him, it's Eric, a delusion of necessity, who becomes his only ally in the pursuit to bring his son home.