While a brother and sister, along with their grandparents, visit the Museum of Fine Arts, the balloon they were not allowed to bring into the museum floats around Boston, causing a series of mishaps at various tourist sites.
In this wordless story, a young girl and her grandmother view works inside the Metropolitan Museum of Art, while the balloon she has been forced to leave outside floats around New York City causing a series of mishaps that mirror scenes in the museum's artworks.