SHE escaped the shackles of Oxford Castle and made off into the snow disguised under a white cloak.

But 871 years later ‘Empress Matilda’ returned to the scene of her former imprisonment to help with a royal quest.

The interactive Easter event, Oxford Castle – Unlocked, tells the story of the daughter and heir of King Henry I.

Treasure hunters must seek out coins and help Matilda claim victory against her foe King Stephen and the crown of England.

Oxford resident Tracy Slator said: “It’s always huge fun to play her. She is quite majestic and a busy character and you can do a lot with her. I’m the same age as she was when she escaped – 42!”