There's a new arrival - a mysterious and exotic young princess - at court and Lady Grace can't believe how many rumours there are about her already.
The exiled Banoo Yasmine from Sharakand is a beautiful girl with a pet panther and - everyone believes - magical powers. Yasmine also possesses the renowned Heart of Kings Ruby - a huge stone that she wears around her neck to balls and feasts, that legend says has the power to make kings.
When the famed jewel goes missing, the finger is pointed at Grace's dear friend Ellie the laundrymaid. Grace must prove her friend's innocence, find the true thief and restore the stone to its rightful owner.