In this new adventure, Maluquinho is spending the holidays at the home of his grandfather Tônico (Stênio Garcia), an inventor who lives in a small community in the interior of Minas Gerais. His friends Junim (Samuel Brandão), Lucio (Cauã Bernard Souza), Bocão (João Romeu Filho) and Nina (Fernanda Guimarães) are coming to the city to help Maluquinho organize the circus for the centenary of the city. On this trip, they meet Tatá-Mirim, a small flame that ends up making the city believe that they are being invaded by the Capeta. So they end up living many adventures.

The Nutty Boy tells the story of a mischievous young boy living in Brazil during the 1960s. He explores his surroundings, gets into trouble, and dreams of exciting adventures. With a pot on his head, he embarks on a series of hilarious escapades that involve school, cooking, dancing, and even peeing. The movie captures the innocence and curiosity of childhood, as well as the importance of family.