In 1958, Cate Archer (while she was the thief known as "The Fox") infiltrated Cramble Castle with the intent to swap the Robin's Egg jewel with a fake one. She bribed a servant with a bottle of Glen Rothes who provided her with the fake jewel and left a window open for Archer to use.
Archer utilized her Safe Cracker to get past the security system in place within the castle. After she made the swap, the ghost known as the Grey Servant opened up a secret passage which allowed Archer to escape with the real jewel.
- It was never revealed if the theft of the Robin's Egg was ever discovered or what Archer did with the real Robin's Egg.