On a sunny afternoon in late June, Cambridge professor Joseph Reavley is summoned from a student cricket match to learn that his parents have died in an automobile crash. Joseph’s brother, Matthew, as officer in the Intelligence Service, reveals that their father had been en route to London to turn over to him a mysterious secret document—allegedly with the power to disgrace England forever and destroy the civilized world. A paper so damning that Joseph and Matthew dared mention it only to their restless younger sister. Now it has vanished.

Spring, 1918. The Great War is at a crucial stage, the Germans are making one last push into France, and the Allies are struggling to hold them back. Battle lines are shifting, and men, and their machines, are being sent up and down the front to shore up defenses. Major Heathcliff Lennox, and his batman Greggs, are told to report to their new HQ. They set off on a sunlit day to fly the distance, but the enemy is never far away, and disaster strikes. They're sent crashing to the ground behind enemy lines, where life, death, and love await.

His name, they tell him, is William Monk, and he is a London police detective. But the accident that felled him has left him with only half a life; his memory and his entire past have vanished. As he tries to hide the truth, Monk returns to work and is assigned to investigate the brutal murder of a Crimean War hero and man about town. Which makes Monk’s efforts doubly difficult, since he’s forgotten his professional skills along with everything else.

When a maid in the upper class Ellison household is strangled, Inspector Pitt is called in to investigate. He finds a world ruled by strict manners and social customs, where the inhabitants of the Ellison's neighborhood appear to be more outraged by the thought of scandal than they are by murder. Inspector Pitt finds a most unlikely ally in Charlotte, the Ellison's spirited daughter. But as the murders continue, Charlotte and Pitt find themselves drawn together by more than the investigation.

On vacation from London on the beautiful Italian coast, 28-year-old Elena Standish and her older sister Margot have finally been able to forget some of the lasting trauma of the Great War. Touring with her camera in hand, Elena has found new inspiration in the striking Italian landscape, and she's met an equally striking man named Ian. Not ready to part from one another, she and Ian share a train trip home to England. But a shocking murder disrupts their agenda, forcing Elena to personally deliver a message to Berlin that could change the fate of Europe.

Arriving in Constantinople in 1273, Anna Zarides vows to prove the innocence of her twin brother, Justinian, who has been exiled to the desert for conspiring to kill a nobleman. Disguising herself as a eunuch named Anastasius, Anna moves freely about in society, maneuvering close to the key players involved in her brother’s fate, including Zoe Chrysaphes, a devious noblewoman with her own hidden agenda, and Giuliano Dandolo, a ship’s captain conflicted by his growing feelings for Anastasius.

Molly Murphy always knew she'd end up in trouble, just as her mother predicted. So, when she commits murder in self-defense, she flees her cherished Ireland, under cover of a false identity, for the anonymous shores of late 19th-century America. When she arrives in New York and sees the welcoming promise of freedom in the Statue of Liberty, Molly begins to breathe easier. But when a man is murdered on Ellis Island, a man Molly was seen arguing with, she becomes a prime suspect in the crime.

The year is 1861. The American Civil War has just begun, and London arms dealer Daniel Alberton is becoming a very wealthy man. His quiet dinner party seems remote indeed from the passions rending America. Yet investigator William Monk and his bride, Hester, sense growing tensions and barely concealed violence.

Mariah Ellison, Charlotte Pitt's grandmother, accepts her longtime friend Winnie's gracious invitation to spend Christmas with her and her husband, Barton, in their picturesque village. But upon arrival, Mariah discovers that Winnie has vanished without a trace, and Barton rudely rescinds the invitation. Once Mariah finds another acquaintance to stay with during the holiday season, she begins investigating Winnie's disappearance.

It's Christmas and the well-born guests who have gathered at Applecross for a delicious weekend of relaxation are warmed by roaring fires, mistletoe, and gorgeously wrapped gifts. It's scarcely the setting for misfortune, and no one - not even that clever young aristocrat and budding sleuth Vespasia Cumming-Gould - anticipates the tragedy that is to darken this light-hearted holiday house party. But soon one young woman lies dead, a suicide, and Vespasia must uncover the heartbreaking truth behind the tragedy.