McGarrett must contend with Honore Vashon, who wants revenge for his son's death.

Dominick Vashon, the patriarch of the clan, makes his attempt to bring down McGarrett and Five-O.

McGarrett becomes involved with the Vashon mafioso family after the youngest member, Chris, is implicated in a daring raid on a hotel.

When a singer witnesses a murder committed by a racketeer, Five-O has to protect her until she can give evidence, but this is not an easy job...

Wo Fat is suspected of being behind the theft of a mobile ICBM device, and McGarrett with other top officials must stop him selling it off to the highest bidder.

A crazed electronics wizard threatens the lives of a psychiatrist and his patients by using electronic devices and gadgets.

A writer who specialises in solving mysteries uncovers the body in a seven year old case, but it raises more questions than it answers...

Five-O is up against a sophisticated gang who have come to Hawaii to cash $750,000 of traveller's cheques.

A policeman who was kicked off the force blames McGarrett and Five-O and plans to kill the Governor.

A veteran criminal who has already had dealings with Five-O escapes, and plans to steal millions of dollars from drug smugglers.

When a letter bomb kills a Naval Officer whilst McGarrett is on Navy Duty, he is called upon to investigate and uncovers a plot involving an old nemesis...

McGarrett and company must pit their wits against a veteran thief and robber who leaves Monopoly money at the scene of his crimes.

When a young woman is beaten and raped and a soldier is arrested for the crime, McGarrett begins to have doubts about his guilt.

A local thug, Piro Manoa, is trying to create the impression of corruption in the Five-O force, and Duke is implicated in a murder. McGarrett and the team, with new recruit Ben Kokua, must save Duke's position and work out the plot of the organisation behind the false accusations.

A husband and wife team of scam merchants get caught between some of Hawaii's most powerful mobs.

Chin Ho and Dan Williams are tracking a safecracker but he pulls a gun and Danno ends up shooting him. McGarrett takes his identity of Harry Brown and must infiltrate a sophisticated gang of international thieves.

McGarrett is framed in an elaborate set up by Wo Fat, and has to contend with a foreign double amongst other problems.

McGarrett sets up a cordon of police around a young woman to capture her boyfriend who has escaped from jail, but all is not as it seems…

A young widow becomes part of a blackmail plot involving the murder of a Chicago mobster.

McGarrett must try his utmost to foil Wo Fat's plans which include hostages and brainwashing.

When a singer, Joey Rand, finds that his career doesn't pay well enough, he turns to cat burglary. However he doesn't reckon on Hawaii Five-O.

When the boxing son of a policeman, Phil Kalama, is killed, he starts a personal vendetta, and McGarrett must both solve the crime and stop Kalama from committing another murder.

Five seemingly good citizens with different motives band together to steal $6,000,000 while McGarrett is away on Maui at a trial.

Three real estate crooks die horrible and mysterious shellfish related deaths, and McGarrett and the others must establish the link between them, and who has reason to want them dead.

A psychotic man named Ralston is killing the wives of members of his army unit, and Five-O, including Kono on his last case, must stop him before he commits any more crazed attacks.