Four misfits find themselves struggling with ordinary problems when they are suddenly pulled through a mysterious portal into the Overworld, a bizarre, cubic wonderland that thrives on imagination. To get back home, they'll have to master this world while embarking on a magical quest with an unexpected, expert craftier. Together, their adventure will challenge all five to be bold and to reconnect with the qualities that make each of them uniquely creative-the very skills they need to thrive back in the real world.

Set on a colorful Greek island, the plot serves as a background for a wealth of ABBA songs. A young woman about to be married discovers that any one of three men could be her father. She invites all three to the wedding without telling her mother, Donna Sheridan (Meryl Streep), who was once the lead singer of Donna and the Dynamos. In the meantime, Donna has invited her back-up singers, Rosie Mulligan (Dame Julie Walters) and Tanya Wilkinson (Christine Baranski).