4x1 - The Hoodlum

October 5, 1959

A racketeer's bookkeeper gets Diamond involved in a blackmail scheme against his boss, when he asks him to find a book and gives him only one hour to do so.

4x2 - Act of Grace

October 12, 1959

An acquaintance of Diamond's is murdered. At his grave at a potter's field, Diamond sees a wealthy old woman laying flowers at some of the unmarked graves. Diamond tries to find the connection between her and his down-on-his-luck friend.

4x3 - The Bookie

October 19, 1959

A bookie decides to get rid of Lt. Kile, whose efforts to put a stop to the bookie's operation have begun to annoy him.

4x4 - The Client

October 26, 1959

A financier hires Diamond to search for his partner who has gone missing in Mexico.

4x5 - The Runaway

November 2, 1959

While briefly stopping in San Francisco, Diamond finds himself the target of a gunman.

4x6 - No Laughing Matter

November 9, 1959

Diamond finds himself in a deserted amusement park on the trail of a desperate fugitive murderer.

4x7 - The Messenger

November 16, 1959

Diamond is hired to deliver a note to a bank teller and is somewhat surprised when the teller screams after she reads the note.

4x8 - The Counselor

November 23, 1959

A marriage counselor whose life has been threatened hires Diamond to protect him.

4x9 - The Image

November 30, 1959

An old nemesis of Diamond's on the police force has Diamond arrested on murder charges after the girlfriend of an escaped convict is found murdered.

4x10 - The Adjustor

December 7, 1959

Diamond receives a tip that a man who has been presumed dead for over a year is still alive.

4x11 - Marked for Murder

December 14, 1959

Diamond finds himself in a lonely hearts club when he is hired to investigate the confusing circumstances surrounding a robbery and murder.

4x12 - The Caller

December 21, 1959

Diamond receives a mysterious telephone call which informs him that he will die at a specific time later that evening.

4x13 - One Dead Cat

December 28, 1959

A night club singer hires Diamond to protect her and her band leader from a disgruntled pianist who once played in their band.

4x14 - Dead to the World

January 11, 1960

A friend of Sam's wants Diamond to prove that her uncle's death was murder.

4x16 - The Fine Art of Murder

January 25, 1960

An actress hires Diamond after she learns that a valuable painting which she purchased is a fake.

4x17 - The Popskull

June 28, 1960

Diamond follows a dog which is pursuing a bedraggled cat.

4x18 - And Whose Little Baby Are You?

July 5, 1960

After returning to his apartment with a date, Diamond finds an infant abandoned on his couch.

4x19 - Fallen Star

July 19, 1960

A journalist hires Diamond to look into the death of a singer who fell to her death, which he suspects was a murder but that the police have ruled a suicide.

4x20 - Coat of Arms

August 2, 1960

A landlady finds one of her tenants dead in his room and shortly afterwards is greeted by a gun-wielding stranger looking for the man.

4x21 - Double Trouble

August 9, 1960

A diplomat who does not want the police to be involved, asks Diamond to find his missing fiancee.

4x22 - The Lovely Fraud

August 16, 1960

Shortly after a dancer takes out a large insurance policy on her legs, she gets injured by a hit and run driver and is forced to collect on the policy.

4x23 - Accent on Murder

August 23, 1960

A woman is killed after hiring Diamond to protect ""a young lady from France"" who turns out to be a poodle.

4x24 - East of Danger

August 30, 1960

A woman hires Diamond when her father is attacked after he finds heroin hidden in his antique store warehouse.

4x25 - Running Scared

September 6, 1960

A man is concerned about his daughter, whom he feels has been spending too much time brooding over her husband's death.

4x26 - The Mouse

A French woman gets threats from a supposedly dead war criminal who knows the whereabouts of a fortune in smuggled diamonds.