Six months have passed since Dr. Ogden moved to Buffalo and Det. Murdoch is constantly a loggerheads with Dr. Francis, her replacement. While Insp. Brackenreid thinks highly of Francis, who was recruited from Scotland Yard, Murdoch finds him stubborn and unimaginative. He also seems to be in no rush to help Murdoch with his latest case where human body body parts were discovered on a riverbank encased in cement. A homeless man living in the woods nearby is questioned and released and Murdoch corresponds with Dr. Ogden who offers him valuable advice in her letters. He also gets help from a retired detective, Malcolm Lamb. Murdoch connects his current investigation a rape and murder that had occurred many years before.

Det. Murdoch investigates a series of deaths among members of a Toronto military regiment. All were in the same squad under the command of British Maj. Gregory Bole, on loan to train them in a new kind of warfare using what's called kommando tactics. When Murdoch learns that the men had signed a tantine agreement where the last man living would inherit all of the others investments, he thinks he's identified the killer, Matthew Larson who resigned from the regiment a few months before. It's not that simple however and when Murdoch learns that others in the squad are all hospitalized with a mysterious disease, he has to look to a training assignment they undertook in South Africa earlier in the year.

Ignoring a puzzling break-in at Station 4, Murdoch travels to Buffalo to help Dr. Ogden solve the suspicious death of a young cancer patient at a children's hospital.

Dark secrets surface at the Jenkins household when Murdoch questions the family and servants of murdered patriarch Percival Jenkins.

Det. Murdoch investigates the disappearance of Monique Poirier, a young French woman who was in Toronto visiting her sister Sophie. She had returned to her room at the hotel to get her camera but then just vanished into thin air. Also in town is a handsome young police Inspector from France, Marcel Guillaume, also looking for someone. They first suspect Sophie's husband, Roderick Dalewood, but photos suggest his own sexual appetites lay elsewhere. The case is further complicated when they find the body of a young woman in a steamer trunk, badly burned with acid. Murdoch has a new way of getting a photograph sent to him by wire. Insp. Brackenreid meanwhile is approached by a group of businessmen to run for city council. There is a price however for his support.

While attending an agricultural show, Detective Murdoch is amazed at the quality and detail of a miniature street scene that is on display. It includes several houses and several miniature residents. It also includes a man standing in a second floor room pointing a rifle. Murdoch quickly concludes that he is looking at the recreation of a murder scene. He quickly finds the Toronto neighborhood depicted in the model and learns that it was created by Lydia Howland, an idiot-savant who does not speak but has a photographic memory. He is certain that she witnessed a murder and now has to figure how to get at her memories and determine which of the people depicted in the miniature is the real-life killer.

Det. Murdoch and Const. Crabtree investigate when a body is uncovered by workmen. The remains are quite old and date from perhaps the mid-1860s. Dr. Ogden's review of the remains indicate that he might have been murdered. Among the remains is a gin flask with a note secreted in a false bottom. The note is signed by none other than the man who would later become Canada's first Prime Minister, Sir John A. MacDonald. The dead man is soon identified and Murdoch's old nemesis from Ottawa, spook Terence Meyers, is on the scene as well. A surprise visitor to the station gives them vital information about the theft of $1 million in gold and a connection to the U.S. Civil War.

name of Pip. Dr. Ogden determines that the boy was strangled with something that left a unique mark on the his neck. She also notes that he was wearing a proper and quite new suit of clothes, something odd for a boy who lived on the street. Their investigation leads them to another young boy named Dorrie. It seems pretty clear that the children are the bottom rung of a gang that specializes in burglarizing homes while the occupants are away on holidays or business trips. The police are assisted throughout by a young telephone operator, Tess Moffatt, who would love to be an investigator. Meanwhile Inspector Brackenreid hits the campaign trail in his quest for a seat on city council.

Det. Murdoch investigates the shooting death of a New York City man on a Toronto streetcar. He was shot in the stomach but no one heard a shot. Back at the station, he's surprised to find his friend from Bristol, Anna Fulford, who has come to Toronto via New York city with her fiancé and are on their way to Niagara Falls to be married. He's vanished however and Anna is naturally worried. Soon after confirming that the dead man is not her fiancé, someone takes a shot at her. After making enquiries with the New York City police, Murdoch learns of a new kind of criminal organization known as the Black Hand. Insp. Brackeneid meanwhile is uncomfortable when his political backer orders him to get rid of a band of gypsies that are camping in the woods.

Just as the Sisters in a Toronto religious convent are about to bury one of their own, they see that there is already a body in the grave. Det. Murdoch investigates but is shocked to find that his sister Susannah is the Mother Superior. They had not seen each other for 20 years when she left for convent school as a 14 year-old eventually joining a cloistered order. She had received a dispensation from her vow of silence and has been in Toronto for five months, something that disturbs William as she had not contacted him. The dead man was wearing a clerical collar but is later identified as a crook with a criminal record. Murdoch finds the place on the convent grounds where the man was murdered and is convinced that the killer is to be found among the religious sisters.

Detective Murdoch investigates the death of a young female student attending a residential boarding school in Toronto. She was found on the school grounds in a fountain and Dr. Ogden confirms that she drowned. Somewhat ominously, she has several cuts and the doctor confirms she had lost 3 pints of blood. She also has what appears to be two bite marks on her neck. Constable Crabtree, who has been reading Dracula by Bram Stoker is convinced they have a vampire on the loose. Murdoch looks for a more realistic explanation and finds that several other girls at the school have been going out late at night and meeting a handsome young man - and who they too claim is a vampire.

Toronto is hit with a series of bank robberies where the lone gunman not only takes the money but kisses a pretty girl before running off. Pesky Toronto Gazette reporter Patty Glenn is all over it which is proving to be more sensational than the the recent vampire stories. Oddly however, the stolen money turns up on the doorstep of a local orphanage. When the thief robs the same bank for a second time and kisses the same girl, Annabelle Rose, Murdoch begins to suspect that he may have taken a particular liking to the girl. When the bandit robs the bank for a third but kills Annabelle with a revolver, Murdoch thinks he may have the solution. Meanwhile, Dr. Julia Ogden's vivacious sister, Ruby, is back in Toronto to attend Julia's upcoming marriage to Dr. Darcy Garland. She's not convinced that Julia and William no longer have feelings for one another.

A man is found murdered at a Lewis Carroll costume party. All clues point to the guest dressed as the Mad Hatter.