|The One That Got Away|
|Directed by||Seith Mann|
|Written by||Robert Doherty|
|Air date||29 January, 2015|
|Previous||"The Illustrious Client"|
As Kitty begins to unravel due to the imminent threat to her safety, Sherlock and Joan intensify their efforts to help her. Also, the origin of Sherlock and Kitty's relationship is revealed. Stuart Townsend guest stars.