When things get rocky for the Conroy family, Ruth, Naomi, Rachel, and Phoebe are sent off to stay with their grandmother in Cumbria for the summer. Considering Big Grandma gives orders like a drill sergeant, makes the girls do chores, and refuses to keep books in the house, their summer away sounds like a recipe for disaster. Set on having a great summer together, the sisters decide they simply won't take Big Grandma's strict rules and chores, stirring up loads of chaos in the process. But as they set out to discover alternative ways of entertainment, the four sisters begin to understand why their grandmother lives how she does--and Big Grandma slowly begins to understand them.