The Mighty Muskrats are off to the city to have fun at the Exhibition Fair. But when Chickadee asks Grandpa what he would like them to bring back from the city, she learns about Grandpa's missing little sister. She was, they learn, scooped years ago--like many Indigenous children, the government had arranged for her adoption by strangers without her parents' permission. Now the Mighty Muskrats have a new case to solve: uncovering the whereabouts of Grandpa's long-lost sister. Once in the bright lights of the big city, the cousins get distracted, face off with bullies, meet some heroes and unlikely teachers, and experience many of the difficulties Indigenous kids often face in the city. Their search for their missing auntie takes them all the way to the government and reveals hard truths about their country's treatment of Indigenous kids and families.