Thirteen-year-old Mark Rogers knew that his Grandpa Luigi had Alzheimer's but he hadn't counted on it turning his life upside-down. When his mother suggests that the two of them move in with Grandpa and help care for him, Mark reluctantly agrees because his grandfather has always been something of a hero to him. He doesn't know, however, how strange Grandpa's behaviour has become or that the kids in his new school have a nickname for him: Crazy Luigi.