Sherlock Holmes is alive again, and Molly Hooper can see that something has changed him profoundly. As she begins to realize that the change in his behavior is mostly evidenced in his interactions with her, she also starts to suspect that she has more to do with the cause of his transformation than she would ever have imagined - even if she doesn't know how or why.

If Molly Hooper were a case, Sherlock Holmes would have just come to the disturbing realization that there was a possibility that his incomplete research had led to a wrongful conviction. Left alone in Molly's flat, Sherlock's exploration and the discoveries he makes challenge his previously held notions and assumptions about the woman who helped him cheat death.