E1 - The Young Assassins

Aired: September 10, 1974

Danno and a college professor are kidnapped by a revolutionary group of young radicals led by a hardened criminal.

E2 - A Hawaiian Nightmare

Aired: September 17, 1974

A geophysics expert, Bernard Brown, is heavily in debt, so he comes up with a plan to cause an explosion in the Hawaii Volcanoes National Park, which will cause lava to pour all down the hillside and into the city of Hilo, unless the Governor comes up with half a million dollars as a ransom.

E3 - I'll Kill 'Em Again

Aired: September 24, 1974

Eddie Josephs is a paranoid schizophrenic who is carrying out murders based on old Five-O cases. McGarrett must follow his clues and catch him before more people die.

E4 - Steal Now -- Pay Later

Aired: October 01, 1974

A sophisticated thief is selling his goods to legitimate businessmen, and Five-O must find a way of trapping him.

E5 - Bomb, Bomb, Who's Got The Bomb?

Aired: October 08, 1974

Senator Harlan Henderson suffers from multiple personalities, and one side of him wants to kill himself. However, he ends up blowing up his secretary, and McGarrett uses handwriting and a diagnosis from a psychiatrist to try to crack the case.

E6 - Right Grave, Wrong Body

Aired: October 15, 1974

A criminal, Hobart, is robbing liquor stores using a policeman's former gun, but the officer wants it back as he used it to kill a bankrobber five years before and the body has been uncovered.

E7 - We Hang Our Own

Aired: October 22, 1974

When his son is beaten to death, a powerful cattle baron takes matters into his own hands, and McGarrett and Five-O must prevent the rule of law from breaking down.

E8 - The Two-Faced Corpse

Aired: October 29, 1974

A gangland execution investigation takes a turn for the peculiar when it is found that the victim had two identities.

E9 - How To Steal A Masterpiece

Aired: November 12, 1974

Five-O must investigate why three infallible security systems are failing to prevent the theft of priceless artworks.

E10 - A Gun For McGarrett

Aired: November 26, 1974

After an attempt is made on Steve McGarrett's life, he is drawn towards a female art dealer, but she too may not be good for his health…

E11 - Welcome To Our Branch Office

Aired: December 03, 1974

Two conmen use a gang of Five-O lookalikes and doubles to extort money from Honolulu businessmen.

E12 - Presenting... In The Center Ring... Murder

Aired: December 10, 1974

Wo Fat returns to Hawaii in order to have a Chinese diplomat whom he classes as a foolish peace-maker assassinated.

E13 - Hara-Kiri: Murder

Aired: December 31, 1974

McGarrett and Five-O need to find out why a Japanese banker ritually killed himself and catch a true criminal into the bargain.

E14 - Bones Of Contention

Aired: January 07, 1975

A Honolulu murder is mysteriously linked to a human fossil smuggled out of China in the Second World War.

E15 - Computer Killer

Aired: January 14, 1975

An investigation into a murder is sent off track through the modification of computer information, and Five-O must use the latest technology to rescue the case.

E16 - A Woman's Work Is With A Gun

Aired: January 21, 1975

Three women desperately in need of money take to armed robbery of tourist buses as a way to raise some quick cash.

E17 - Small Witness, Large Crime

Aired: January 28, 1975

When a young boy is arrested as a witness to a murder, McGarrett must contend with a fiery deputy public prosecutor.

E18 - Ring Of Life

Aired: February 04, 1975

A million dollar reward for the return of five figurines sparks off a trail of murder and theft that leads to Hawaii.

E19 - Study In Rage

Aired: February 11, 1975

When a psychotic man kills his doctor, Five-O must use a unfinished painting to gather clues to his whereabouts.

E20 - And The Horse Jumped Over The Moon

Aired: February 18, 1975

An elaborate sea and air scheme for heroin smuggling goes unnoticed until one of the gang tries to sell out their plan for a fix of heroin.

E21 - Hit Gun For Sale

Aired: February 25, 1975

McGarrett must prevent a mob war by tracking down an unknown hitman and his intended target.

E22 - The Hostage

Aired: March 11, 1975

When a deranged ex-Army officer shoots a policeman and takes a young girl hostage, McGarrett disagrees with a police captain over the best way to free her.

E23 - Diary Of A Gun

Aired: March 18, 1975

A Saturday Night Special passes from person to person and causes Five-O trouble and others misery.

E24 - 6,000 Deadly Tickets

Aired: March 25, 1975

Five-O works with a air traffic investigator in order to put a stop to illegal ticket sales which have already cost several lives.