Victorian adventuress and butterfly hunter Veronica Speedwell receives an invitation to visit the Curiosity Club, a ladies-only establishment for daring and intrepid women. There she meets the mysterious Lady Sundridge, who begs her to take on an impossible task - saving society art patron Miles Ramsforth from execution. Accused of the brutal murder of his artist mistress Artemisia, Ramsforth will face the hangman's noose in a week's time if Veronica cannot find the real killer. But Lady Sundridge is not all that she seems.

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.

Victorian adventuress Veronica Speedwell is whisked off to a remote island off the tip of Cornwall when her natural historian colleague Stoker's brother calls in a favor. On the pretext of wanting a companion to accompany him to Lord Malcolm Romilly's house party, Tiberius persuades Veronica to pose as his fiancée. But upon arriving, it becomes clear that the party is not as innocent as it had seemed. Every invited guest has a connection to Romilly's wife, Rosamund, who disappeared on her wedding day three years ago, and a dramatic dinner proves she is very much on her husband's mind.

Autumn 1888. Veronica Speedwell and her colleague Stoker are asked by Lady Wellingtonia Beauclerk to stop a potential scandal so explosive it threatens to rock the monarchy. Prince Albert Victor is a regular visitor to the most exclusive private club in London, and the proprietress, Madame Aurore, has received an expensive gift that can be traced back to the prince. Lady Wellie would like Veronica and Stoker to retrieve it from the club before scandal can break.

January 1889. As the newest member of the Curiosity Club - an elite society of brilliant, intrepid women - Veronica Speedwell is excited to put her many skills to good use. As she assembles a memorial exhibition for pioneering mountain climber Alice Baker-Greene, Veronica discovers evidence that the recent death was not a tragic climbing accident but murder.

Fresh from a six-month sojourn in Italy, Lady Julia returns home to Sussex to find her father's estate crowded with family and friends: but dark deeds are afoot at the deconsecrated abbey, and a murderer roams the ancient cloisters.

In Grimsgrave Hall, enigmatic Nicholas Brisbane has inherited a ruined estate, replete with uncanny tenants and one unwanted houseguest: Lady Julia Grey. Despite his admonitions to stay away, Lady Julia arrives in Yorkshire to find Brisbane as remote and maddeningly attractive as ever. Cloistered together, they share the moldering house with the proud but impoverished remnants of an ancient family: the sort that keeps their bloodline pure and their secrets close.

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 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. With the New Year’s Eve ball approaching fast and the hotel’s reputation hanging by a thread, Cleo must find the killer before the ball, and the hotel itself, are ruined. 

Lady Julia Grey travels through India, accompanied by her sister, Portia, her brother, Plum, and occasionally her husband - Brisbane. Along the way, Portia becomes convinced of a murder, and all four are pulled into the dark underbelly of 19th-century India....

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.

As "Sherlock Holmes, consulting detective," Charlotte Holmes has solved murders and found missing individuals. But she has never stolen a priceless artwork - or rather, made away with the secrets hidden behind a much-coveted canvas. But Mrs. Watson is desperate to help her old friend recover those secrets and Charlotte finds herself involved in a fever-paced scheme to infiltrate a glamorous Yuletide ball where the painting is one handshake away from being sold and the secrets a bare breath from exposure.

Edinburgh, Scotland. March 1832. Kiera and Gage have been eagerly awaiting their bundle of joy but trouble has been brewing in the form of the roguish criminal Bonnie Brock Kincaid. A new book and subsequent play features some of Kincaid's daringly heinous exploits, although he swears he had nothing to do with it or the characters which are obvious representations of Kiera and Gage. A rash of crimes break out across the city, seemingly inspired by the play and book. Then the publisher is found brutally murdered.

Inspector Treadles, Charlotte Holmes’ friend and collaborator, has been found locked in a room with two dead men, both of whom worked with his wife at the great manufacturing enterprise she has recently inherited. Rumors fly. Had Inspector Treadles killed the men because they had opposed his wife’s initiatives at every turn? Had he killed in a fit of jealous rage because he suspected Mrs. Treadles of harboring deeper feelings for one of the men? To make matters worse, he refuses to speak on his own behalf, despite the overwhelming evidence against him. 

. Mister Slaughter opens in the emerging metropolis of New York City in 1702, and proceeds to take both Matthew and the reader on an unforgettable journey of horror, violence, and personal discovery. The journey begins when Matthew, now an apprentice problem solver for the London-based Herrald Agency, accepts an unusual and hazardous commission. Together with his colleague, Hudson Greathouse, he agrees to escort the notorious mass murderer Tyranthus Slaughter from an asylum outside Philadelphia to the docks of New York.

Brisbane has taken charge of the music. Julia has, perhaps mistakenly, allowed her sisters to choose the dress. And Belmont Abbey is overflowing with guests awaiting the blessed day. What could go wrong? Combine the close-knit chaos of village life, pagan traditions bursting through staid Victorian conventions, and the congenial madness that tends to swirl around Lady Julia's family and you get an unforgettable wedding.