When a beautiful young woman is murdered, Holmes and Watson investigate her ties to a billionaire CEO. Meanwhile, Mycroft makes a case for Sherlock to move back to London.

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 fellow recovering addict.

When a famous cancer researcher is found dead, Holmes and Watson must determine if the scientist’s untimely demise was tied to his latest cutting-edge invention. Meanwhile, Bell is finally cleared to re-enter the field.

Holmes and Watson come into contact with MI-6, the British intelligence agency, when a standard murder investigation turns out to have international and political implications. Meanwhile, in the wake of a crisis, Watson reevaluates her relationships with Sherlock and his brother, Mycroft.

When Sherlock and Joan join forces on a double homicide, Sherlock’s new apprentice threatens the investigation when she allows her jealousy of Sherlock and Joan's work rapport to override her better judgment.

Holmes and Watson search for a thief who committed murder to steal a rare map. Meanwhile, Watson becomes concerned with Sherlock’s escalating interference into Kitty’s burgeoning personal life.

Holmes and Watson follow a blood trail into the world of wrongful death compensation when they investigate a series of murders in which the killer leaves envelopes of cash on the victims. Also, Holmes makes a generous gesture towards Watson as she suffers through the aftermath of a personal crisis.

When Sherlock finds himself distracted by his father’s ongoing presence in New York City, he offers to help Morland resolve a work issue in exchange for his prompt departure home. Also, Holmes and Watson’s investigation into the double murder of two men who looked alike leads them into the world of facial recognition technology.

Holmes’ tentative reconciliation with his father suffers a setback when Holmes and Watson discover Morland has been keeping a secret that threatens all of their safety. Also, Holmes and Watson investigate two murders connected to a for-profit college and its illegal recruitment practices.

When a survivalist doctor goes missing, Holmes and Watson must determine whether he’s purposely gone off the grid or if he’s a victim of foul play. Holmes exhibits odd behavior when his romantic relationship with Fiona hits a critical point.

Sherlock’s father, Morland, becomes Sherlock and Joan’s prime suspect in a murder investigation after one of his employees is killed under the guise of a robbery.

Captain Gregson lobbies to include Holmes and Watson when his unit is selected to receive a city commendation for its exemplary work. Also, as Holmes and Watson consult on the investigation into a financial analyst’s murder, they are drawn into the world of asteroid research.

When Watson is implicated in a DEA investigation into doctors writing illegal prescriptions, she and Holmes search for the person using her medical license to sell drugs.

The police call in Holmes and Watson to consult on a homicide “heard” by a cutting edge gunshot detection system when they can’t find any tangible evidence that a crime was committed. Also, Sherlock and Joan become suspicious of Shinwell when he’s the target of a drive-by shooting that reveals a connection between him and an unsolved murder.

When Detective Bell’s girlfriend, Chantal, is assaulted and her ex-husband is killed soon after, in what Holmes and Watson discover is a staged suicide, they search for one suspect behind the linked crimes. Also, as Bell fights the urge to seek his own brand of justice for Chantal, Sherlock makes a heartbreaking realization about the detective’s past.

As Holmes confronts a medical diagnosis that threatens both his career and sobriety, he meets Michael, a man who credits Sherlock for helping him conquer his own addiction. Also, Holmes and Watson are hired by a reformed party girl heiress to find her missing partner in a years-old sex tape that has just leaked online.

Holmes engages an old foe to protect his father after he learns Morland is in danger of being killed. Also, Holmes and Watson search for a killer connected to the tobacco industry when a lawyer who was in the process of reviewing a major cigarette distributor’s finances is murdered.

Holmes and Watson investigate the poisoning of a relocation expert and discover the man led a decades-long secret career as a contract killer before his death. Also, Watson’s path to adopting a child suffers a setback as she prepares for a home visit from her agency case worker.

Holmes and Watson search for an ulterior motive when Cassie Lenue, a brilliant young criminal they helped put in prison, seeks their help in solving a murder.

Holmes and Watson join forces with Holmes’ father, Morland, to enlist his vast criminal network to help disassemble tech billionaire Odin Reichenbach’s crime prevention system.