Betrayal in time / Julie McElwain.

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Kendra Donovan's adventures in nineteenth-century England continue when she is called upon to investigate the murder of a spymaster.

February 1816: A race through the icy, twisting cobblestone streets of London ends inside an abandoned church--and a horrific discovery. Bow Street Runner Sam Kelly is called to investigate the grisly murder of Sir Giles Holbrooke, who was left naked and garroted, with his tongue cut out. Yet as perplexing as that crime is, it becomes even stranger when symbols that resemble crosses mysteriously begin to appear across the dead man's flesh during autopsy. Is it a message from the killer?

Sam turns to the one person in the kingdom who he believes can answer that question and solve the bizarre murder--the Duke of Aldridge's odd but brilliant ward, Kendra Donovan.

While Kendra has been trying to adapt to her new life in the early nineteenth century, she is eager to use her skills as a twenty-first century FBI agent again. And she will need all her investigative prowess, because Sir Giles was not an average citizen. He was one of England's most clever spymasters, whose life had been filled with intrigue and subterfuge.

Kendra's return to the gritty streets and glittering ballrooms of London takes her down increasingly dangerous paths. When another body is discovered, murdered in the same apparently ritualistic manner as Sir Giles, the American begins to realize that they are dealing with a killer with an agenda, whose mind has been twisted by rage and bitterness so that the price of a perceived betrayal is death.

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Publishers Weekly Review

In McElwain's outstanding fourth mystery set in Regency England (after 2018's Caught in Time), the authorities ask FBI profiler and time traveler Kendra Donovan, the American ward of the Duke of Aldridge (one of only two people to know she's from the future), to look into the strangling murder of English spymaster Sir Giles Holbrooke, who was found lying naked on the floor of an abandoned London church with his tongue cut out. During the autopsy, bizarre markings slowly appear all over Sir Giles's body, possibly forming a message from the killer. Kendra and her detection team, which includes a Bow Street runner and an irreverent journalist, get on a trail that leads them deep into family jealousies and foreign espionage-and to more ritualistic murders. One of the series' delights is how Kendra, who operates with a shocking degree of independence for a single woman in the era, must repeatedly find ways to use her forensic knowledge and instincts about homicide that don't send polite society reaching for the smelling salts. With perfect pacing, McElwain holds the reader's interest from the first page to the last. Agent: Jill Grosjean, Jill Grosjean Literary. (July) © Copyright PWxyz, LLC. All rights reserved.

Booklist Review

This unusual, absorbing tale drops readers into 1816 London, a setting the main character was herself dropped into when time-transported from the present-day U.S. An FBI agent in her former life, Kendra Donovan is now the ward of the Duke of Aldridge, who knows of her origins while most don't, and who enlists her in solving the murder of another member of the gentry. Well-integrated story lines involve Kendra's romance, which suffers feminism-meets-chivalry tensions, and a grief-stricken family whose son's fate is an education in the horrors of war. The highlight here, however, is the time-travel aspect, which sees FBI investigatory skills muted to match the knowledge and mores of the day. While the novel can stand alone, for maximum enjoyment, readers should first tackle the earlier books in the series (A Murder in Time, 2016; A Twist in Time, 2017; Caught in Time, 2018), which explain how Kendra finds herself in the past (one hopes they also explain the use of the anachronism unsub, which the nineteenth-century characters in this book inexplicably understand).--Henrietta Verma Copyright 2019 Booklist

Kirkus Book Review

A time-traveling FBI agent is more celebrated for her forensic skills than her social ones.Even though it's no picnic to be stuck in 1816 England, Kendra Donovan is fortunate to have become the ward of the Duke of Aldridge, who passes her off as the daughter of an old friend and the lover of his nephew, Alexander Morgan, the Marquis of Sutcliffe, who is indeed keen to marry her. Both men, fascinated by her knowledge, try to help her adjust to a very different world in which her outspokenness often lands her in trouble. Having already solved one murder case (Caught in Time, 2018), she's a natural choice for Bow Street Runner Sam Kelly to call on when Sir Giles Holbrooke is found naked with his tongue cut out in an abandoned church. Sir Giles was both a spymaster and an adviser to the prince regent, and his death is sure to cause shock waves. His body was covered with a crosslike symbol written in invisible ink that became visible only when the heat of the lanterns used during his autopsy brought them out. Reporter Phineas Muldoon hints that politics and the Irish problem may be involved. Then again, Gerard Holbrooke, a spoiled young man deep in debt, may have killed his father to escape being shipped off to India. The sleuths discover that Sir Giles' long friendship with the family of apothecary Bertel Larson ended in disaster when Sir Giles convinced their brilliant son Evert to spy for him and he was killed in an incident in France that left Lord Eliot Cross and Capt. Hugh Mobray the only survivors. Kendra finds both the parents and their son David bitter over Evert's death. When Cross is murdered in the same way as Sir Giles, the members of the Larson family become prime suspects. But Kendra senses something fishy about the story of how Evert died and knows she must dig deeper in search of the truth.A much improved mystery, a touch of history, and the obligatory romance combine for a pleasing read. Copyright Kirkus Reviews, used with permission.