While on suspension from the NYPD, Sherlock investigates a suspicious hit-and-run accident involving a conspiracy theorist. Meanwhile, Watson tries to broker peace between Sherlock and Gregson.

When Captain Gregson’s home is invaded, Holmes and Watson work to find the masked gunman before he strikes again. Meanwhile, Gregson gives his team some insight into his private life.

A bored Sherlock forces his investigative services onto Joan, who is trying to locate a woman who has been missing for five years, and the only clue is the smell of nutmeg at the site of her disappearance. Meanwhile, Joan’s bond with her long-distance boyfriend, Andrew, is tested when a man from her past reappears and asks for her help.

When a debt collector is murdered, Holmes and Watson try to narrow down the suspect pool from thousands of consumers who owed the victim money. Meanwhile, Watson’s relationship with Andrew progresses when he asks her to meet his father for the first time.

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 and Watson investigate a homicide in which the victim was murdered in a manner reminiscent of the crimes of an infamous, and already incarcerated, serial killer. Also, Sherlock and Joan tutor Detective Bell for a police sergeant’s exam that would lead to a promotion and a post at another precinct.

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.

When a serial bomber becomes active again after being dormant for six years, Watson seeks help from Shinwell Johnson, a former patient whose life she saved when she was a surgeon. Also, Holmes senses Watson is unhappy and questions whether she is still fulfilled by her detective career.

Joan and Kitty try to prove that a string of murders, stemming from an old case Sherlock and Kitty solved in London, is connected to an international government conspiracy with the Defense Intelligence Agency at its center. Also, Sherlock and Kitty’s relationship is strained after she shares life-changing news.

When Holmes and Watson investigate a murder, they find themselves in the crosshairs of one of New York City's deadliest gangs. Holmes' behavior becomes increasingly erratic when he secretly interacts with a mysterious woman.

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 and Watson enter the world of rare antiquities when they investigate a case in which victim was killed during a Revolutionary War reenactment. Also, as Holmes grows frustrated with the length of his cognitive recovery, he finds solace in his growing friendship with Michael.

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’s investigation into the murder of a religion professor puts them on the hunt for a killer connected to the occult. Also, Holmes and Watson curate a list of potential replacements for Detective Bell when it looks likely the officer will be asked to join the U.S. Marshal Service.

Holmes and Watson race to locate a missing woman when Harlan Emple, Holmes’ friend and “Irregulars” mathematics expert, becomes the prime suspect in her disappearance.

Holmes and Watson face their greatest challenge to date when a murder investigation threatens to destroy their partnership.

Amidst Holmes and Watson’s battle with tech billionaire Odin Reichenbach, the investigators receive word of their old enemy and Sherlock’s former love, Jamie Moriarty.