A psychologist is found stabbed to death in a seemingly sealed room. Inspector March needs to decide who had the most reason to kill him, and how did they accomplish the task.

Colonel March's niece, a believer in spiritualism, thinks she hears her dead husband's voice and others in the house become convinced her husband has returned as a ghost. But has he?

A French fashion model asks for Colonel March's help, claiming a strange man is following her and she fears for her life. Several hours later she's found murdered, in mismatched colour, a telling clue for the inspector.

Members of the Himalayan Mountaineering Club are threatened by what appears to be the abominable snowman, and someone leaves a strange footprint on a ledge outside Colonel March's office.

While on holiday in France, there is a murder at the docks and Colonel March is asked by a friend of the French police to assist. The only clue left behind by the culprit, a sailor's cap - "looking for the head that fits this hat."

At an isolated château outside Paris, a scientist insists he's received radio waves emanating from Mars. Seeking a way to suspend a person's life functions during space travel, his volunteer subject dies from lack of oxygen. Accident or foul play?

Colonel March and Inspector Goron are present in a café when a customer dies from poisoned wine and the waiter falls under suspicion because he was a former chemist.

A scientist conducting cancer research is convinced that his test monkey was not only stolen but replaced. He is later found dead from gas, and Colonel March must prove if it was suicide or not.

Behind the "silver curtain" spray from a fountain, a man is found dead with a knife in his back. Colonel March is called in to investigate.

A shady businessman collapses on an oceanside jetty, the apparent victim of a heart attack, but a vacationing March discovers blood and a needle near the body. A little boy's lost ball may be the key to a possible murder.

A skull, known as the Damascus man, is stolen from a museum and Colonel March's life is imperiled trying to solve the case.

A 15th century prayer volume disappears from a sealed casket inside the locked safe belonging to an Oxford Don. An illusionist is called in to demonstrate how the book can disappear from a locked safe, when the supernatural is suspected.

A pretty barmaid receives an unusual Christmas gift, a music box from a thief, dead ten years. But someone is soon murdered searching for something valuable hidden in the mysterious gift and Colonel March believes the music holds the key.

A phony spiritualist believes she's truly summoned a real ghost. Colonel March attends her next seance to discover the identity of the spirit's killer - dead or alive.

Murder and blackmail culminate in this episode where a call for help during a Javenese dance is the clue that Colonel March needs to prove a faulty alibi.

Colonel March receives a queer complaint that a pair of disembodied gloves killed a man. He refuses to give up easily despite the fact there is no corpse, no blood, and no evidence of wrongdoing.

A woman is found dead, but was it suicide or murder? A French fencing match provides the telling clue and Inspector Goron travels to London to assist Colonel March.

Colonel March is called in to investigate the theft of a valuable diamond as well as the kidnapping of a little boy's poodle. As the investigation continues, he begins to think both incidents may be connected.