Penelope Platypus must face the reality of growing up and moving out of the family burrow. Her parents have given her notice that it is time for her to move out and to begin a burrow and family of her own. Devastated by their decision, Penelope falls into a deep sadness at a time when the river animals are very excited about the annual River Dance. But through her deep sadness and depression, Penelope learns that she has many wonderful friends of the river delta who support her through this difficult time. And, in the end, Penelope enjoys the big dance!