The manager of a high-end hotel that caters to diplomatic VIPs is found dead in the hotel's laundry. After first suspecting a connection to a prostitution ring, Holmes believes the answer lies in her treacherous past.
Sherlock is called in on a case and immediately recognizes the work of an old foe from Britain. Sherlock sees it as a chance at redemption in catching the man, but first he needs to control his own emotions about the murderer.
Holmes discovers a man running an internet conspiracy site is dead. As he follows the chain of clues, he becomes aware of the "Red Team" and the trail leads him further down the rabbit hole than he ever imagined.
A convicted killer who is supposed to donate a kidney to his sister ends up killing the surgical staff before escaping. Holmes is forced to work with a profiler (whom he can't stand) because she supposedly can predict what he will do next.
Holmes' former drug supplier comes to him for help to find his kidnapped daughter. He agrees to help him despite Watson's protests. When Holmes appears stymied, the former dealer encourages Holmes to go back on drugs, hoping it will help him solve the case.
Detective Bell is nearly killed while driving home one night. A just-released felon is the first suspect but, when he's killed, suspicion moves to Bell's brother who, unlike the dedicated detective, has lived life on the wrong side of the law.
A wealthy scientist comes to Holmes with a unique case: he believes he has been "poisoned" with a genetic disorder. Holmes has to determine how a healthy person can be contaminated with a genetic disease that no one in his family has.
Watson works a case on her own about a woman who has disappeared while Holmes deals with a subway murder. As they work their separate cases they gradually appear to be connected, even though they can't determine exactly how.
In the middle of a winter storm, Holmes and Watson must solve the murder of a guard during a botched robbery and unravel the killer's true plan. The pair also get an interesting new roommate.
A blackmailer uses tapes of underage girls to get money from their fathers. When Holmes witnesses the blackmailer's murder, it becomes a race to find out who his accomplice is and prevent the videos from being released on the Internet.
A man connected to the classification of a valuable building as a landmark trust dies when his pacemaker is deliberately short circuited. Holmes soon learns the one behind the murder is an old nemesis known to him only as "Moriarty".
Moriarty asks Holmes to find out who murdered a mechanic in Brooklyn. Despite Watson's protests, Holmes thinks this case will help him uncover Moriarty's true identity, but it will, in fact, lead Holmes to something much worse.
Holmes reconnects with Irene, his one true love that he thought had been taken from him by Moriarity. He tries to protect her as she recovers from her trauma but he soon learns that it isn't she that needs protection.
While recovering from his gun shot wounds, Holmes eschews painkillers while working on a case of a Greek shipping magnate - involving an assassination and currency manipulation - before his final showdown with Moriarty.
When a well-respected mathematician is found dead, Holmes and Watson set out to solve a murder and the purpose of the highly guarded equation he was trying to decipher.
When Holmes and Watson set out to track down a civil contractor who leaked classified information, their lives are disrupted when they are targeted by the group of cyber-activists protecting him. Tony Award Winner Steve Kazee guest stars.
Sherlock's brother, Mycroft, arrives in New York and enlists Holmes and Watson to help solve a case involving his former fiancee. Meanwhile, Sherlock has a difficult time accepting Mycroft and Joan's relationship.
When an investigation goes horribly wrong, Sherlock must testify in an official police inquiry which jeopardizes his and Watson's future with the NYPD.
When a hedge fund manager who was also running a pyramid scheme is murdered, Holmes and Watson must determine which of his clients is guilty. Also, Sherlock contemplates sponsoring a fellow recovering addict.