Pearl is an ordinary girl - but she has a very extraordinary secret. She is a real sea princess! When Pearl searches in her wardrobe for something warm to wear she accidentally falls into the Underwater Kingdom and transforms into a beautiful princess. But there's an emergency going on under the sea. Princess Velvet has been swept up on a tidal wave all the way from their enemies in the Reef Kingdom. Can Pearl befriend the poorly princess and make her better? Princess Pearl brings together all the essential elements of a little girl's imagination - princesses, friendship and a touch of magic!