The McKennas are a middle-class family who are coping with the sudden passing of their beloved patriarch, Patrick. Though devastated, they find hope in the form of a book called 'The Dangerous Book for Boys' that Patrick created for his three sons.

Patrick's book becomes a how-to guide that inspires fantasies in his youngest son, Wyatt, enabling him to reconnect with his father and learn lessons that help him navigate the real world.