Sherlock and John are investigating a case, when they find a girl named Hannah in one of Jim Moriarty's old bases. She is rather aggressive, but more importantly, she does not speak properly. At the same time, this girl could be able to reveal many of Jim Moriarty's secrets. Can Sherlock and John befriend this mysterious girl and learn to communicate with her?

Gregory Lestrade and Mycroft Holmes finally meet. There appears to be an instant yet mysterious chemistry...