Holmes and Watson investigate the murder of a man Sherlock considered one of New York’s worst private investigators. Also, as Holmes stews over being beaten by Shinwell, he decides to take out his aggression by dismantling a local organization of private investigators.

When a reality show contestant is murdered, Holmes and Watson zero in on another competitor as a suspect, a former war criminal who may be the most skilled killer they’ve ever pursued. Also, for the first time since he attacked Sherlock, Shinwell reaches out to Joan to ask for a favor

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.

Holmes and Watson investigate a murder that initially looks like a road rage incident, but takes a new direction when they learn the victim was flash-frozen at the time of death. Also, when Watson’s mother finds out Joan’s brother is cheating on his wife, she puts Joan in the awkward position of confronting him about the affair.

When an archeologist is murdered, Holmes and Watson believe the man may have been killed for what he discovered during his last excavation in a local landfill. Also, Sherlock’s relationship with Alfredo, his friend and former sobriety sponsor, hits a rough patch.

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.

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.

Holmes and Watson must search for a killer without any physical evidence to aid them after a bomb is detonated in the New York City morgue. Also, Watson is suspicious when an NYPD detective she’s in a grudge match with asks her to consult on a case.

When Holmes’ investigation into the attempt on Morland’s life pushes their strained relationship to the breaking point, the identity of Sherlock’s mother is revealed. Also, when three gang members are murdered, Holmes and Watson are amazed when an elderly woman emerges as their prime suspect.

Holmes and Watson investigate the murder of a former professional eSports video game player who died after being assaulted in front of his fans during a live video stream. Also, Shinwell approaches Joan for advice when his teenage daughter asks to meet with him for the first time in years.

Holmes and Watson get mixed up in murder and magic when they investigate the death of a magician killed while performing a classic stunt. Also, Watson suspects Bell is being targeted by the ex-husband of his girlfriend, Chantal, after a false allegation lands him the middle of an Internal Affairs investigation.

Sherlock and Joan investigate the murder of a criminal who made his living by stealing from other criminals. When Gregson resumes leadership of the precinct, he suspects his interim replacement is responsible for one of his best detective’s suspicious departure.

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 find themselves in the middle of a civil war being fought on the Internet when a member of Everyone, the anonymous hacker group they periodically work with, is murdered.

When Morland offers to use his influence to have Sherlock and Joan reinstated as consultants to the NYPD, Sherlock’s mistrust of his father makes him question his motivation to help. Also, with no work offers coming in, Watson wrangles a gig with the FBI investigating a triple homicide in a top secret research lab.

When Watson runs into Captain Gregson and his secret girlfriend, a former NYPD officer, she inadvertently sets the couple’s breakup in motion. Also, Holmes and Watson investigate the murder of a wealthy woman who left her considerable estate solely to a beloved dog.

After a vigilante dressed up as a comic book hero is murdered, Holmes and Watson need to find the man's true identity and find his killer.

When Holmes and Watson are pulled into a double-homicide investigation, they discover the victims were staging a fake murder right at the moment they were killed. Also, Watson's inside man at Morland's office encounters a problem that threatens to expose her spying to Holmes and his father.

Sherlock and Joan question how well they know Shinwell when they investigate the possibility he may have gotten away with the unsolved murder of his friend, a fellow gang member. Also, Sherlock and Joan’s latest case puts them on the hunt for a treasure map rumored to lead to a fortune in pirate’s gold hidden around New York City.

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.

Detective Bell considers leaving the NYPD when he is recommended for a once-in-a-lifetime career opportunity. Also, Holmes and Watson are hired by a private client to investigate the disappearance of a young woman who led a double life online as a financial dominatrix.

Sherlock and Joan investigate the murder of the general manager of a high-end Manhattan hotel whose body is found inside an industrial laundry machine. Meanwhile, since Joan’s time with Sherlock is almost up, he offers her an apprenticeship.

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 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. Meanwhile, Joan takes the advice of a friend and signs up for an online dating service.

Holmes and Watson find themselves digging through the dark world of the mob to find a killer when they discover the body of a former assassin. Meanwhile, Watson helps a close friend track down a mystery man who swept her off her feet.