London, 1898—A vibrant young heiress has gone missing, and it’s up to Sherlock and Lucy to find her. Meanwhile, threatening letters from Egyptian revolutionaries begin turning up at newspaper offices, captivating Sherlock’s interest, and sparking public fear and outrage.

Then the missing young woman is found dead in front of London’s most famous Egyptian monument. Are the dangerous radicals may be making good on their threats? But when suspicion falls on the dead woman’s husband, the Baker Street team find themselves grappling for the truth.

As they dig deeper into the mystery, they uncover a dastardly and deadly plot that puts them all in danger. And when one of their own falls prey to an evil deception, they must act quickly to prevent disaster.

Can the Baker Street team catch the wily killer and save their imperiled friend? Or will all of their best efforts turn to ruin?