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. 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.

Watson and her half sister, Lin, have conflicting reactions when their estranged biological father dies. Holmes and Watson find themselves on the hunt for a stolen plutonium shipment they fear will be used to make a dirty bomb after a Department of Energy inspector is killed with a lightning gun.

Holmes and Watson enter the world of rare antiquities when they investigate a case in which victim was killed during a Revolutionary War reenactment. Holmes finds solace in his growing friendship with Michael.

Watson considers making a major life change after reading her own therapy file while Holmes and she investigate the murder of her former psychologist.

Holmes and Watson retrace Holmes’ steps after he finds himself in possession of a severed head and no memory of the past six hours or why he has it.

Holmes and Watson enter the world of nuclear security when they investigate the murder of an ex-Yakuza gang member. Captain Gregson is blindsided by a stunning personal confession from his police sergeant daughter.

Holmes and Watson find themselves on the hunt for a serial killer after a murder rocks their inner circle. Holmes’ neurological recovery regresses and his sobriety wavers as his commitment to catching the killer grows into an obsession.

Holmes and Watson’s search for the killer of a woman found encased in cement takes them inside the clean technology industry. Watson takes a giant leap forward regarding her interest in adoption.

Holmes’ former sobriety sponsor, Alfredo, asks for his help with an illegal endeavor in order to save his brother. Holmes and Watson investigate the poisoning of a biology professor who was working on a secret genetics project prior to being killed

Sherlock and his father attempt to repair their strained relationship upon learning of a death within their family. Holmes and Watson discover a link between their latest case and the world of Egyptian antiquities when they search for a killer who tried to mummify his victim.

Holmes engages an old foe to protect his father after he learns Morland is in danger of being killed. 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.

Detective Bell considers leaving the NYPD when he is recommended for a once-in-a-lifetime career opportunity. 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.

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. 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 race to help Detective Bell when he becomes a victim of a bio-terrorism attack at the precinct and the station is quarantined. During the lockdown, Captain Gregson and Detective Bell begin to suspect they are trapped inside with the perpetrator. Watson faces the difficult task of helping her mother, Mary, accept that her advancing Alzheimer's disease requires her to receive more medical care.

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 discover that the murder of a robotics engineer may be connected to his groundbreaking secret research in the area of real-life teleportation. Also, when Detective Bell is shut out of a required class he needs in order to complete his master's degree and join the U.S. Marshal Service, he is shocked to discover the course instructor has personal reasons for denying him access.

Holmes and Watson investigate multiple motives for murder when a zoologist is killed because of his numerous love affairs or his trailblazing research. Also, Holmes finds himself the victim of identity theft after his medical records are stolen.

Holmes and Watson search for a killer choosing victims based on the predictions of a deceased man who claimed to foresee the future deaths of others, including the murder of Sherlock Holmes.

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’s deadly conflict with Sherlock’s former friend Michael intensifies when their newest victim looks to be the serial killer’s latest prey.

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

Sherlock's and Joan's new careers as consultants for Scotland Yard in London take them inside the tabloid journalism industry when a popular model is the victim of an acid attack. As Joan grows increasingly homesick for New York, Gregson is wracked with guilt over his unresolved rift with his former consultants.

Sherlock and Joan try to work a stateside investigation from London when someone close to them in the U.S. is gravely wounded by an unknown perpetrator. Sherlock’s stateside legal trouble threatens to derail their efforts.

Sherlock takes extreme measures to secure his return to New York when he leans on his father’s disreputable connections to aid his legal re-entry into the United States. Joan helps the NYPD investigate a murder at a storage facility that caters to wealthy clients with items they want hidden from U.S. Customs.

An explosion at a traffic stop puts Sherlock and Joan on two separate tracks of investigation as they try to determine whether the attack was gang-related or a terrorist attack. Sherlock and Joan suspect there is more for them to discover regarding the recent attack on someone within their inner circle.

Tech billionaire Odin Reichenbach hires Sherlock and Joan to investigate a personal threat he suspects originated from within his own company. Sherlock and Joan search for a motive behind three seemingly unconnected murders.

Tech billionaire Odin Reichenbach presents Sherlock and Joan with an extraordinary offer to help him with a program that can predict future crimes. Sherlock and Joan assist Bell when he tries to prevent a future crime of his own, as he races to locate a fellow NYPD officer planning a sniper shooting.

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.

Sherlock and Joan search for an ulterior motive when a brilliant young criminal they helped put in prison, seeks their help in solving a murder.

Sherlock and Joan work to determine if a long dormant serial killer has resurfaced in the wake of a sculptor’s murder in New York City. Joan suspects Sherlock is keeping something from her regarding tech billionaire, Odin Reichenbach.

Sherlock and Joan receive a shocking request to collaborate from Reichenbach, who asks them to test his new crime prevention system. Tasked with investigating someone the program predicts will soon commit a crime, the duo worries Reichenbach will take drastic action before they conclude their inquiry.

Sherlock and Joan join forces with Holmes’ father, Morland to enlist his vast criminal network to help disassemble Reichenbach’s crime prevention system.

Reichenbach inadvertently provides Sherlock and Joan with a lead that could give them evidence that brings him to justice.

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