When a hedge fund manager who was also running a Ponzi scheme is murdered, Holmes and Watson must determine which of his clients is guilty. Also, Sherlock contemplates sponsoring a…

Joan discovers an unsolved murder connected to a rare prehistoric fossil when she reviews one of Sherlock’s cold cases; Sherlock’s responsibilities as a sobriety sponsor cross personal boundaries.

Shaw must stay close to a 10-year-old girl with highly developed surveillance skills when she is identified by the machine; Carter’s mission could be exposed.