Sequel to The Thinker Challenge. Sherlock returns to London with Sio, helping her recover from the ordeal in Bahrain. They navigate the ins and outs of a faux marriage while confronting family, friends and old flames. As the dust settles, Sherlock begins to suspect that all is not as it seems with Sio and that her memory of events in Bahrain may not be entirely reliable.

Loki tells the story of the early days of his arranged marriage to an Olympian queen.

The Thinker Challenge offers a prize of 2 million to the first group to create a working prototype capable of transcribing the thoughts of a human being directly into a visually accessible form. Its intellectual sponsor, Dr. Sio Stanton, is a prickly astrophysicist with ambiguous motives who, after hiring Sherlock Holmes on a whim decides to make him an interesting offer.