Detective Murdoch investigates the death of Oliver Hoyle who is found in the billiard room of his posh club. Hoyle was part of a group of competitive puzzle solvers and he may have been killed after solving a puzzle published by Edgar Allen Poe many years ago. It appears that one of his competitors killed him to get the glory for himself. Meanwhile, Julia visits her father Lionel but arrives only to learn that her father has died. His physician, Dr. Bradley, believes he died of heart failure sometime in the night. Julia is confused, particularly when Dr. Bradley refuses to undertake an autopsy. Murdoch soon joins her and initially doubts that anything illegal has happened. He reconsiders when he learns that Julia has found a needle mark in her father's neck and a new neighbor is the beneficiary in his will.

As Murdoch seeks a promotion, a constable is shot in a botched raid on an opium den led by Watts.

Murdoch suspects John is being framed for murder by Inspector McWorthy and Brackenreid goes after the corrupt copper.

A visiting vaudeville show has a grotesque murder and a young comedian, Charles Chaplin, may have been the intended target by the killer who is intent to finish the job.

While the Murdochs investigate a series of murders at a country inn while on vacation, Crabtree and Higgins investigate a beheaded accountant in a community garden.

A woman who was sentenced to a bridal version of British penal transportation is found dead in the dorm of such female convicts.

Murdoch's investigation of a murder at an opium den intersects with Brackenreid's pursuit of Nomi's missing friend.

The brutal murder of a woman from Murdoch's past complicates his life.

Reeling from a personal revelation, Murdoch seeks to avenge the murder of Anna Fulford.

Dr. Ogden proceeds with an unorthodox operation. Murdoch must outwit the Black Hand and return his son to Anna Fulford. George needs to break away from his captors. The real family member missing from an Asian family is determined.

Murdoch investigates the suspicious death of a stage manager after a going away party for Mary Pickford.

Murdoch's son Harry is visiting from boarding school when Julia and William are abducted by a vengeful foe

A charity basketball game turns grim for Murdoch and his colleagues when a friend of the game's inventor is murdered

When a man resembling Murdoch is shot, he must find the killer before the killer finds him.

With his family in hiding, Murdoch tries to discover who is behind attempts on their lives.

Crabtree bails on his marriage plans after a prophecy; Murdoch investigates the bizarre murder of two gravediggers.

Murdoch suspects Hart is lying about her father's death. Brackenreid leads a PI to Watts endangering both their futures.

As Murdoch investigates the murder of an elite athlete impaled by a javelin, Hart and Arthur plot her father's demise.