Ruth Bussey once did something horribly wrong, and was nearly destroyed by her punishment. Now, she has tentatively rebuilt her life and unexpectedly found love with Aidan Seed. But Aidan also has a secret--he killed someone years ago, a woman named Mary Trelease. Ruth's horror turns to confusion when she realizes that she knows Mary Trelease, and Mary is very much alive. Set in London's vibrant art scene, and featuring the return of Sergeant Charlotte...

While traveling from London to Kingfisher Hill to discretely investigate murder allegations against a wealthy client's wife, Hercule Poirot swaps seats with a nervous train passenger before a second killing is complicated by a series of impossible confessions.