Thirteen-year-old Lady Grace Cavendish, maid of honor to Queen Elizabeth I, describes in her diary how she tries to discover who stole a magical ruby belonging to the visiting princess of Sharakand.

When one of her fellow Ladies-in-Waiting becomes mysteriously ill, Lady Grace Cavendish suspects the cause is poison and sets out to learn who is responsible. There is much excitement at Court as the famous painter Levina Teerlinc arrives to paint the Queen's portrait. The Maids of Honor are recruited to help entertain the Queen during the sittings, and to pose for the painter while the Queen is busy. They love being in the studio but have to beware...