The mysterious lady is a female equine caretaker played by Uniqua. She assists the Adventurer's Club by guiding Adventurer Tyrone. She is later revealed to be the guardian of the flying polka-dotted pony.
The mysterious lady is mostly pink. She wears a light gray-purple dress, with a red hood and and a red-and-blue sash.
Uniqua has played the mysterious lady in one episode of The Backyardigans: "Follow the Feather" from season four.