The gruesome murder of a young French physician draws aristocratic investigator Sebastian St. Cyr and his pregnant wife, Hero, into a dangerous, decades-old mystery as a wrenching piece of Sebastian’s past puts him to the ultimate test. Regency England, January 1813: When a badly injured Frenchwoman is found beside the mutilated body of Dr. Damion Pelletan in one of London’s worst slums, Sebastian finds himself caught in a high-stakes tangle of murder and revenge. Although the woman, Alexi Sauvage, has no memory of the attack, Sebastian knows her all too well from an incident in his past—an act of wartime brutality and betrayal that nearly destroyed him. As the search for the killer leads Sebastian into a treacherous web of duplicity, he discovers that Pelletan was part of a secret delegation sent by Napoleon to investigate the possibility of peace with Britain. Despite his powerful father-in-law’s warnings, Sebastian plunges deep into the mystery of the “Lost Dauphin,” the boy prince who disappeared in the darkest days of the French Revolution, and soon finds himself at lethal odds with the Dauphin’s sister—the imperious, ruthless daughter of Marie Antoinette—who is determined to retake the French crown at any cost. With the murderer striking ever closer, Sebastian must battle new fears about Hero’s health and that of their soon-to-be born child. When he realizes the key to their survival may lie in the hands of an old enemy, he must finally face the truth about his own guilt in a past he has found too terrible to consider....

In this mystery in the Sebastian St. Cyr series, the aristocratic investigator is drawn into a sordid world of greed, desperation, and the occult when the husband of his former lover is accused of murder. Regency England, September 1812: After a long night spent dealing with the tragic death of a former military comrade, a heart-sick Sebastian learns of a new calamity: Russell Yates, the dashing, one-time privateer who married Kat Boleyn a year ago, has been found standing over the corpse of Benjamin Eisler, a wealthy gem dealer. Yates insists he is innocent, but he will surely hang unless Sebastian can unmask the real killer. For the sake of Kat, the woman he once loved and lost, Sebastian plunges into a treacherous circle of intrigue. Although Eisler’s clients included the Prince Regent and the Emperor Napoleon, he was a despicable man with many enemies and a number of dangerous, well-kept secrets—including a passion for arcane texts and black magic. Central to the case is a magnificent blue diamond, believed to have once formed part of the French crown jewels, which disappeared on the night of Eisler’s death. As Sebastian traces the diamond’s ownership, he uncovers links that implicate an eccentric, powerful financier named Hope and stretch back into the darkest days of the French Revolution. When the killer grows ever more desperate and vicious, Sebastian finds his new marriage to Hero tested by the shadows of his first love, especially when he begins to suspect that Kat is keeping secrets of her own. And as matters rise to a crisis, Sebastian must face a bitter truth—that he has been less than open with the fearless woman who is now his wife.

When Gabrielle Tennyson is murdered, aristocratic investigator Sebastian St. Cyr and his new reluctant bride, the fiercely independent Hero Jarvis, find themselves involved in an intrigue concerning the myth of King Arthur, Camelot, and a future poet laureate...

It's September 1811, and someone is killing the wealthy young sons of London's most prominent families. Partially butchered, with strange objects stuffed into their mouths, their bodies are found dumped in public places at dawn. When the grisly remains of Alfred, Lord Stanton's eldest son are discovered in the Old Palace Yard beside the House of Lords, the local magistrate turns to Sebastian St. Cyr, Viscount Devlin, for help. Ranging from the gritty world of Thames-side docks to the luxurious drawing rooms of Mayfair, Sebastian finds himself confronting his most puzzling--and disturbing--case yet. With the help of his trusted allies--young servant Tom, Irish doctor Paul Gibson, and his lover Kat Boleyn--Sebastian struggles to decipher a cryptic set of clues that link the scion of a banking family to the son of a humble Kentish vicar. For as one killing follows another, Sebastian discovers he is confronting a murderer with both a method and a purpose to his ritualized killings, and that the key to it all may lie in the enigmatic stanzas of a haunting poem...and in a secret so dangerous that men are willing to sacrifice their own children to keep the truth from becoming known.

Hero Jarvis, reform-minded daughter of the Prince Regent's cousin, enlists Sebastian St. Cyr's help in investigating the brutal murders of eight prostitutes. Following a trail of clues from London's seedy East End to the Mayfair mansions of a noble family, the two must race against time to stop a killer whose ominous plot threatens to shake the nation to its very core?

In Brighton, England, in 1811, when the wife of an aging marquis is found dead in the arms of the Prince Regent, wearing an ancient necklace with mysterious ties to Sebastian St. Cyr, Sebastian turns sleuth to investigate the woman's death.

Sebastian St. Cyr thought a notorious killer had been brought to justice until a shocking series of gruesome new murders stuns the city in this thrilling historical mystery from the USA Today bestselling author of Who Speaks for the Damned. It's October 1814. The war with France is finally over and Europe's diplomats are convening in Vienna for a conference that will put their world back together. With peace finally at hand, London suddenly finds itself in the grip of a series of heinous murders eerily similar to the Ratcliffe Highway murders of three years before. In 1811, two entire families were viciously murdered in their homes. A suspect--a young seaman named John Williams--was arrested. But before he could be brought to trial, Williams hanged himself in his cell. The murders ceased, and London slowly began to breathe easier. But when the lead investigator, Sir Edwin Pym, is killed in the same brutal way three years later and others possibly connected to the original case meet violent ends, the city is paralyzed with terror once more. Was the wrong man arrested for the murders? Bow Street magistrate Sir Henry Lovejoy turns to his friend Sebastian St. Cyr, Viscount Devlin, for assistance. Pym's colleagues are convinced his manner of death is a coincidence, but Sebastian has his doubts. The more he looks into the three-year-old murders, the more certain he becomes that the hapless John Williams was not the real killer. Which begs the question--who was and why are they dead set on killing again?