After purchasing an old blackened brooch at a garage sale, Harriet discovers that it is a valuable piece of jewellery and was part of a collection that Henry VIII gave to each of his wives. Further intrigue mounts as she learns that the brooch was stolen from Lord Denham in 1840 by a houseboy, George Millard. He is convicted of theft and transported to Australia.

Harriet pursues her investigations until she has proof of who actually stole the brooch and travels to London to have the case re-opened by the British courts.