New York, 1924. Vivian Kelly's days are filled with drudgery, from the tenement lodging she shares with her sister to the dress shop where she sews for hours every day. But at night, she escapes to The Nightingale, an underground dance hall where illegal liquor flows and the band plays the Charleston with reckless excitement.

London 1815. Newly widowed Lily Adler is returning to a society that frowns on independent women. At a ball thrown by her oldest friend, Lady Walter, she expects the scandal, gossip, and secrets. What she doesn't expect is the dead body in Lady Walter's garden. Lily overheard the man just minutes before he was shot: young, desperate, and attempting blackmail. But she's willing to leave the matter to the local constables - until Lord Walter bribes the investigating magistrate to drop the case. Stunned, Lily realizes she's the only one with the key to catching the killer.

December 1899. After the death of her beloved grandmother, Cleopatra Fox moves into the luxury hotel owned by her estranged uncle in the hopes of putting hardship and loneliness behind her. But the poisoning of a guest on Christmas eve throws her new life, and the hotel, into chaos. Cleo quickly realizes no one can be trusted, not Scotland Yard and especially not the hotel’s charming assistant manager.

London, 1861. Samantha Kingston has lived under the control of her overbearing uncle since the death of her parents six years ago. Trapped by the conventions of her gender and social class, she is desperate to find a way out. But when her aunt and uncle are murdered, the freedom she sought seems even further out of reach. A suspect in the crime, she finds herself on the run, unsure whom to trust, lost in the underworld she had only ever read about in the pages of a Dickens novel.

Hours later, the man’s cold body lies in the city mortuary, alongside the woman he couldn’t save. And his sister, unconventional nurse Gemma Tate, tracks down troubled police inspector Sebastian Bell to unravel the truth. Sebastian has enough pressure to solve the murder of an aristocratic heiress without Gemma meddling in his case. But the cryptic sentences she brings him from her brother’s notebook could be a crucial lead. If only they knew what “milky way” meant.

England, 1919. Verity Kent's grief over the loss of her husband pierces anew when she receives a cryptic letter suggesting her beloved Sidney may have committed treason before his untimely death. Determined to dull her pain with revelry, Verity's first impulse is to dismiss the derogatory claim. But the mystery sender knows too much - including the fact that during the war Verity worked for the Secret Service, something not even Sidney knew.

After a routine delivery, midwife Sarah Brandt visits her patient in a rooming house and finds that another boarder, a young girl, has been killed. At the request of sergeant Frank Malloy, she searches the girl's room and discovers that the victim is from one of the most prominent families in New York - and the sister of an old friend. The powerful family, fearful of scandal, refuses to permit an investigation. But with Malloy's help, Sarah begins a dangerous quest to bring the killer to justice before death claims another victim.

Tabitha, Lady Chesterton, the Countess of Pembroke, is newly widowed at only 22 years of age. With no son to inherit the title, it falls to a dashing, distant cousin of her husband's, Jeremy Chesterton, known as Wolf. It quickly becomes apparent that Wolf had consorted with some of London's most dangerous citizens before inheriting the title. Can he leave this world behind, or will shadowy figures from his past follow him into his new aristocratic life in Mayfair? And can Tabitha avoid being caught up in Wolf's dubious activities?

Following the death of her husband, Lady Darby has taken refuge at her sister's estate, finding solace in her passion for painting. But when one of the house guests is murdered, her brother-in-law asks her to aid the insufferable Sebastian Gage - a fellow guest with some experience as an inquiry agent. While Gage is clearly more competent than she first assumed, Kiera isn't about to let her guard down, as accusations and rumors swirl.

London, 1923. Newly minted research assistant Saffron Everleigh is the first woman to hold the position at University College of London. When she attends a dinner party for the school, she expects to engage in conversations about the university's large expedition to the Amazon. What she doesn’t expect is for Mrs. Henry, one of the professors’ wives, to drop to the floor, poisoned by an unknown toxin. Dr. Maxwell, Saffron’s mentor, is the main suspect, and evidence quickly mounts.

It's 1811, and the threat of revolution haunts the upper classes of King George III's England. Then a beautiful young woman is found savagely murdered on the altar steps of an ancient church near Westminster Abbey. A dueling pistol found at the scene and the damning testimony of a witness both point to one man - Sebastian St. Cyr, Viscount Devlin, a brilliant young nobleman shattered by his experience in the Napoleonic Wars.

Twenty-six-year-old Beatrice Hyde-Clare is far too shy to investigate the suspicious death of a fellow guest in the Lake District. A spinster who lives on the sufferance of her relatives, she would certainly not presume to search the rooms of her host's son and his friend looking for evidence. Reared in the twin virtues of deference and docility, she would absolutely never think to question the imperious Duke of Kesgrave about anything, let alone how he chose to represent the incident to the local constable. And yet that's exactly what she does.

Rosalind Thorne may not have a grand fortune of her own, but she possesses virtues almost as prized by the haut ton: discretion, and a web of connections that enable her to discover just about anything about anyone. Known as a "most useful woman," Rosalind helps society ladies in need--for a modest fee, of course--and her client roster is steadily increasing.

England, 1924. Lady Adelaide Compton has recently (and satisfactorily) interred her husband, Major Rupert Charles Cressleigh Compton, hero of the Somme, in the family vault in the village churchyard. Rupert died by smashing his Hispano-Suiza on a Cotswold country road while carrying a French mademoiselle in the passenger seat. With the house now Addie's, needed improvements in hand, and a weekend house party underway, how inconvenient of Rupert to turn up - not in the flesh, but as a spirit! Rupert has to perform a few good deeds before becoming welcomed to heaven.

It’s 1924, and Blix Windway has made a career out of her wanderlust, giving lectures to ladies’ groups about everything from the flora of the American desert to the beauty of the Swiss Alps, but she needs new material for her talks. She strikes what seems to be an ideal agreement with an eccentric older lady. Blix will be her travel companion during a journey to Egypt, helping to smooth the way through customs and coordinate sightseeing tours.