When an NYPD officer is murdered, Holmes and Watson join the investigation. Sherlock looks for the person posting his personal statements made in sobriety meetings on a "recovery blog".
A drug-deprived Thackery fears that a prominent inventor-surgeon will overshadow his accomplishments at the upcoming New York Surgical Society event. Meanwhile, Bertie courts Lucy as he fends off his father's demands that he leave the Knick; and staff members go to court to keep Typhoid Mary in quarantine.moreless
A surprise visit from Sherlock's brother Mycroft leads to discord between Holmes and Watson. Meanwhile, Sherlock and Joan investigate a missing person's case that takes them into the world of unmanned aeronautics.
Mycroft shows up in New York to ask Holmes and Watson to solve a case concerning his former fiancée. Mycroft and Joan's relationship is a source of contention with Sherlock.
When a young man is killed as he enters his apartment, Sherlock is called upon to consult. Watson will have to deal with Sherlock's reaction when she gets together with her ex-boyfriend.