A series of grisly murders rocks London. At each location, only a jumble of bones remains of the deceased, along with a bizarre sphere covered in strange symbols. The son of the latest victim seeks the help of Sherlock Holmes and his former partner, Dr. John Watson. They discover the common thread tying together the murders. Bizarre geometries, based on ancient schematics, enable otherworldly creatures to enter our dimension, seeking to wreak havoc and destruction. 

It is the autumn of 1880, and Dr. John Watson has just returned from Afghanistan. Badly injured and desperate to forget a nightmarish expedition that left him doubting his sanity, Watson is close to destitution when he meets the extraordinary Sherlock Holmes, who is investigating a series of deaths in the Shadwell district of London. Several bodies have been found, the victims appearing to have starved to death over the course of several weeks, and yet they were reported alive and well mere days before.

It’s the autumn of 1890, and a spate of bombings has hit London. The newspapers are full of fevered speculation about anarchists, antimonarchists and Fenians. But one man suspects an even more sinister hand behind the violence. Sherlock Holmes believes Professor Moriarty is orchestrating a nationwide campaign of terror, but to what end? At the same time, a bizarrely garbed figure has been spotted on the rooftops and in the grimy back alleys of the capital.  

Countess Alessandra Zorzi, international adventurer and thief, arrives in Arkham pursuing an ancient body freshly exhumed from a mound in Oklahoma, of curious provenance and peculiar characteristics. But before she can steal it, another party beats her to it. During the resulting gunfight at the Miskatonic Museum, the countess makes eye contact with the petrified corpse and begins an adventure of discovery outside her wildest experiences.

January 1905: Holmes and Watson are summoned by Holmes' brother Mycroft to undertake a clandestine investigation. An agent of the British Secret Service has been found floating in the Thames, carrying a manuscript smuggled into England at the cost of her life. The pages purport to be the minutes of a meeting of a secret group intent on nothing less than taking over the world: the Protocols of the Elders of Zion.