With his father, Sam (Peter Dinklage), in prison and his mother, Natalia (Justina Machado) working long hours at a nursing home, Lenny, age 11, is burdened with the responsibility of looking after his younger brother, Joey, age 7. Lenny plans to celebrate his 12th birthday with friends at Coney Island on the Cyclone roller coaster -- which Joey is too small to ride. Lenny's mother goes to Atlantic City for the weekend and leaves Lenny in charge. When Joey defies Lenny's orders to stay at home, Lenny devises a cruel joke, intending to teach his little brother a lesson. The joke goes too far. Believing that he has shot and killed his older brother, Joey runs away.