Lady Emily is happily married to handsome Colin Hargreave, living quietly with their twin sons, Henry and Richard. Colin is a trusted agent to the Crown and personal favorite of Queen Victoria. Occasionally he is called by the Queen to handle delicate matters that might threaten the Empire. Emily is content with her boys, dogs, and husband, plus she has met the Queen.

A Christmas telegram is received from Jeremy Sheffield, Duke of Bainbridge. He announces his engagement to Miss Amity Wells, an American Heiress. To Emily the news is unexpected and unbelievable. She has been friends with Jeremy since they were three years old, living on adjacent estates. Inseparable as children, they remain close. A confirmed bachelor, living a life of debauchery with total freedom, is what he always talks about. Lady Emily is stunned.

Social climbers and very wealthy parents, Mr. and Mrs. Wells, are delighted their daughter has "caught" a Duke. They will host a two week extravaganza engagement party in the south of France. This will impress society, family and friends and the sky is the limit. Lady Emily and Colin will be coming to the French Riviera to join the festivities and celebrate the betrothed.

The Hotel Britannia, the most fashionable place to stay in Cannes, is gorgeous. Each guest has a suite and after settling in, Emily and Colin go downstairs to meet the others. Jeremy was beaming and the men all liked his fiancé, Amity. Not so the women. His brother Jack kept telling the story about how he introduced them and in a short time Jeremy forgot about his feelings about marriage. Jack says Amity is perfect. That is not the word Emily would use to describe Amity. She has odd feelings around her. What is she missing?

Chauncey Neville, a Harrow school chum of Jeremy, is found dead of an apparent suicide by poisoning. Emily is not convinced and doubts the coroners verdict. Could it be murder? A dancer hired to work at the bachelor's dinner is found murdered the next morning. Strange occurrences involving Jeremy and Emily are happening. Emily is locked in the cell in prison that held the man in the iron mask. Jeremy almost fell off a high cliff while admiring the view from on high. Someone wants to kill one or both of them. Why? Who?

Tasha Alexander creates a daring sleuth in Lady Emily. The Victorian era comes alive from beautiful descriptions of locale and customs. Add a touch of mystery, a cup of tea, and you have a great read by a great author. I loved it.