It is 1864 when Lizzie Martin takes up the post of companion to a wealthy widow who is also a slum landlord. Lizzie is intrigued to learn that her predecessor disappeared, supposedly having run off with an unknown man. But when the girl's body is found in the rubble of one of the recently demolished slums around the prestigious new railway station at St Pancras, Lizzie begins to wonder exactly what has been going on.

When Meredith Mitchell agreed to stay with her actress cousin, Eve, in the run up to Eve's daughter's wedding, she anticipated a degree of drama. But she can hardly have expected it to include murder, blackmail, and unrequited love. Or to involve a certain Chief Inspector Markby, a middle aged divorcee.

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.

When the body of a young woman is discovered in the cowshed of Cricket Farm, the tranquility of the British countryside is shattered. Inspector Jess Campbell is on the case, but with few leads, a grumbling partner, and the new superintendent Ian Carter piling on the pressure, she's beginning to wonder why she chose to be a detective in the first place.

Lady Emily Hardcastle is an eccentric widow with a secret past. Florence Armstrong, her maid and confidante, is an expert in martial arts. The year is 1908 and they've just moved from London to the country, hoping for a quiet life. But it is not long before Lady Hardcastle is forced out of her self-imposed retirement. There's a dead body in the woods, and the police are on the wrong scent. Lady Hardcastle makes some enquiries of her own, and it seems she knows a surprising amount about crime investigation...

The Earl of Wrexford possesses a brilliant scientific mind, but boredom and pride lead him to reckless behavior. He does not suffer fools gladly. So when pompous, pious Reverend Josiah Holworthy publicly condemns him for debauchery, Wrexford unsheathes his rapier-sharp wit and strikes back. As their war of words escalates, London's most popular satirical cartoonist, A. J. Quill, skewers them both.

The daughter of a baronet and minor heiress, Rosalind Thorne was nearly ruined after her father abandoned the family. To survive in the only world she knew, she began to manage the affairs of some of London society's most influential women, who rely on her wit and discretion. So when artistocratic wastrel Jasper Aimesworth is found dead in London's most exclusive ballroom, Almack's, Rosalind must use her skills and connections to uncover the killer.

For Emily, accepting the proposal of Philip, the viscount Ashton, was an easy way to escape her overbearing mother, who was set on a grand society match. So when Emily's dashing husband died on safari soon after their wedding, she felt little grief. After all, she barely knew him. Now, nearly two years later, she discovers that Philip was a far different man from the one she had married so cavalierly.

London, 1878. One April morning, a small boat bearing a young woman’s corpse floats down the murky waters of the Thames. When the victim is identified as Rose Albert, daughter of a prominent judge, the Scotland Yard director gives the case to Michael Corravan, one of the only senior inspectors remaining after a corruption scandal the previous autumn left the division in ruins. Reluctantly, Corravan abandons his ongoing case, a search for the missing wife of a shipping magnate, handing it over to his young colleague, Mr. Stiles.

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.

Mrs. Laetitia Rodd, aged 52, is the widow of an archdeacon who makes her living as a highly discreet private investigator. Her brother, Frederick Tyson, is a criminal barrister living in nearby Highgate with his wife and 10 children. Frederick finds the cases, and Laetitia solves them using her arch intelligence and her immaculate cover as an unsuspecting widow. When a case arises involving the son of the highly connected Sir James Calderstone, Laetitia sets off for Lincolnshire undercover as the family's new governess.

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.

Librarian Sylvia Ashe knows nothing about her past, having grown up without a father and a mother who refused to discuss him. When she stumbles upon a diary that suggests she's descended from magicians, she's skeptical. After all, magicians are special, and she's just an ordinary woman who loves books. She seeks answers from a member of the most prominent family of magicians, but she quickly learns that finding the truth won't be easy, especially when he turns out to be as artless as her, and more compelling and dangerous than books.

As the city prepares to celebrate Queen Victoria's golden jubilee, Veronica Speedwell is marking a milestone of her own. After burying her spinster aunt, the orphaned Veronica is free to resume her world travels in pursuit of scientific inquiry - and the occasional romantic dalliance. As familiar with hunting butterflies as she is fending off admirers, Veronica wields her butterfly net and a hatpin with equal aplomb, and with her last connection to England gone, she intends to embark upon the journey of a lifetime.

Singapore, 1910 - Desperate for a fresh start, Harriet Gordon finds herself living with her brother, a reverend and headmaster of a school for boys, in Singapore at the height of colonial rule. Hoping to gain some financial independence, she advertises her services as a personal secretary. It is unfortunate that she should discover her first client, Sir Oswald Newbold - explorer, mine magnate, and president of the exclusive Explorers and Geographers Club - dead with a knife in his throat.