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.

The episode was rated 7.60 from 1530 votes.

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.

The episode was rated 7.61 from 1539 votes.

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.

The episode was rated 7.62 from 1379 votes.

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.

The episode was rated 7.62 from 1466 votes.

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.

The episode was rated 7.63 from 1470 votes.

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.

The episode was rated 7.64 from 1388 votes.

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.

The episode was rated 7.66 from 1455 votes.

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.

The episode was rated 7.67 from 1862 votes.

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.

The episode was rated 7.67 from 1457 votes.

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.

The episode was rated 7.68 from 1527 votes.

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.

The episode was rated 7.69 from 1385 votes.

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.

The episode was rated 7.69 from 1579 votes.

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.

The episode was rated 7.77 from 1419 votes.

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.

The episode was rated 7.90 from 1468 votes.

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

The episode was rated 8.19 from 1468 votes.