Sherlock Holmes faces a sinister case risking friends' lives. American Amelia joins, seeking her father after her mother's murder. Despite differences, they solve a conspiracy and her mother's case.
Cast: David Thewlis, Blu Hunt, Dougray Scott, Antonio Aakeel, Orén Kinlan, Gia Hunter, Ivana Miličević, Paul Reid
Having unmasked the Red Thread syndicate, Sherlock and Amelia must confront their enemies at the most anticipated debutante ball of the season.
Having cracked the code of the Red Thread's communications network, Sherlock is hot on the path of the kidnap victims, chasing a trail of breadcrumbs that leads all the way to the vaults of the Bank of England.
As Sherlock and Amelia identify the villains surrounding them on all sides, Holmes repays a favor to his oldest enemy, arranging a meeting between Professor Moriarty and the young Australian man who has suddenly become very close to Amelia.
Sherlock searches for the missing jewels and their connection to the kidnapping of his friends; he turns to the insurance investigator, Birtwistle, for his assistance.
Amelia withholds details from Holmes after encountering a charming man with a pistol, but Sherlock must step in when her investigation turns fatal.
Amelia goes under cover to search for clues at Clara's home; Sherlock goes to prison under pretense of meeting his forever foe, Moriarty.
While Sherlock chases a stolen carriage, he sends Amelia on a hunt across London; Amelia has her own ideas and follows her intuition closer to answers but even closer to danger.
Blackmailed and sidelined from investigating, Sherlock Holmes finds hope when a young woman arrives on his doorstep, potentially holding the key to solving the kidnapping of an ambassador's daughter.