The Counterfeit Guest — Rose Melikan

"What I am asking is highly important, but it is not simple. There is the task itself -- gathering information about a man who does not wish his secrets to be disclosed -- and then there is the nature of the work. Spying, even on the enemy, is not a decent job, particularly for a young lady such as yourself."

It is 1797, and Mary Finch, heroine of The Blackstone Key, is now a wealthy heiress. Young ladies in her situation ought to marry well -- as her friend Susannah Armitage has. But is Susannah's marriage to Colonel Crosby-Nash all that it seems? Mary thinks not, and when her suspicions lead to a meeting with the elusive spymaster Cuthbert Shy, he reveals the terrible truth: the colonel is a traitor. At Shy's request, Mary agrees to accompany the Crosby-Nashes to their country estate in order to discover his secrets. It is a perilous assignment, and the danger increases when her only means of communicating with Shy is murderously cut off. If only Mary could contact the redoubtable Captain Robert Holland -- but as he has inexplicably ended their friendship, his help seems out of reach....