Spring, 1833. More consuming than any mystery he has solved is Lord Ambrose's ardor for down-on-her-luck governess Elisabeth Anstruther. To have her hand would bring him untold joy. But when the young lady refuses his proposal, Ambrose smarts from the pain - and has a strange feeling that something awful is soon to unfold.

Elisabeth has taken up a post as companion to nearby Lady Jesmond, but, within days of the girl's arrival, Sir Antony Jesmond's young doctor is poisoned to death. It looks like a simple suicide, but the stopper to the bottle of poison has been painstakingly replaced on the nightstand - something a man in agony could not have done. Elisabeth knows that the one person capable of solving this mystery is Ambrose. And soon, he too is embroiled in the sinister goings-on at Jesmond Place...