Season 1, Episode 24
The first season concludes with McGarrett being framed for the murder of the governor's assistant in a car-bomb explosion, but the evidence suggests that criminal mastermind Wo Fat is responsible and is trying to destroy Five-0. Meanwhile, Danny reunites with his ex-wife and makes plans to return with her to New Jersey.
Five-0 confronts a bioterrorism threat after Danny is exposed to a lethal chemical agent.
A famous fashion photographer (Rick Springfield) who is in Hawaii to shoot a sports magazine's annual swimsuit edition is murdered when his trailer is torched with him inside. The probe reveals the victim was heavily in debt and engaged to be married. Meanwhile, Chin considers lying to investigators to keep his ex-cop uncle from going to prison for stealing $200,000 from the department.
Season 1, Episode 21
The wife of an undercover NYPD detective (Sean Combs) is murdered and he seeks revenge against the crime lord he believes targeted his family. Meanwhile, McGarrett receives an anonymous package that contains photos from his mother's car bombing.
Steve and Danny discover a murder victim while hiking, and Steve suffers injuries when he falls from a cliff during the investigation. The probe reveals the dead man was a local fisherman who was shot and dumped in the mountains. Meanwhile, Kono learns the truth about the scandal that ended Chin Ho's career with the Honolulu police department.
A sci-fi fan dressed like a superhero is thrown from a high-rise hotel window. The investigation uncovers new evidence in a cold-case homicide that may be linked to the current victim. Meanwhile, a CIA agent who has information about the murder of Steve's parents arrives.
Season 1, Episode 18
Danny gets an unexpected visit from his younger brother, Matt (Dane Cook), but Danny soon learns that Matt is the target of an FBI investigation. Meanwhile, a bomber bent on revenge murders a judge's daughter and the probe leads Steve to believe the man isn't through killing yet.
Wealthy college students on spring break are kidnapped and held for ransom by pirates who commandeer the luxury catamaran the group is sailing on. Vanessa Minnillo and Nick Lachey guest star.
Season 1, Episode 16
The lone witness in a high-profile murder case disappears into the jungle when hired assassins attempt to kill her at an FBI safe house. Steve and Chin search for the woman and her pursuers. Meanwhile, Danny's ex-wife and daughter are carjacked and Danny believes his former spouse's husband is involved.
Kai e' e
Season 1, Episode 15
The head of the Tsunami Warning Center mysteriously disappears just as a major tsunami threatens to strike Hawaii and thousands of people are evacuated from the islands.
A high-speed police chase ends with the pursued driver dead and a gruesome discovery of human remains in the suspect's car. The investigation leads to an awkward reunion between Chin Ho and his ex-fiancée.
Season 1, Episode 13
McGarrett's sister is kidnapped and thieves break into Steve's house and steal the evidence surrounding his mother's murder in 1992. The investigation reveals a possible connection between her death and the Japanese mafia, known as the Yakuza.
Chin Ho is abducted and an explosive device is strapped around his neck. The abductor is Victor Hesse, who murdered McGarrett's father, and he demands $10 million and safe passage out of Hawaii or he will kill Chin Ho. When the governor refuses to give Steve the money, he plots to steal the cash from a secret police location.
Season 1, Episode 11
A man is murdered on his honeymoon and his wife is abducted. The investigation reveals the crimes may be linked to a series of unsolved homicides that occurred a year earlier, in which recently married couples were targeted by a serial killer. Also: McGarrett learns a disturbing fact concerning his mother's death.
Season 1, Episode 10
Danny's ex-wife assists Five-0 in a baffling investigation when highly skilled thieves kill two security guards in an armored car heist but leave behind the money.
Season 1, Episode 9
An infamous dictator becomes an assassin's target when he visits the islands. Five-0 must protect him while also investigating the murder of a security guard involved with the visit who apparently knew details of the planned assassination.
Season 1, Episode 8
Danny's ex-partner in the Honolulu Police Department is murdered and his charred body is found in a barbecue pit during a luau. The victim was the focus of an Internal Affairs investigation and was suspected of being a department mole connected to a powerful cocaine cartel.
Season 1, Episode 7
A Navy SEAL suspected of murdering his wife takes hostages aboard the USS Missouri memorial battleship, even though he claims he is innocent. McGarrett uses his own naval training to board the ship and confront the man. The investigation reveals the victim is a former Russian citizen who fled her homeland under mysterious circumstances.
The CEO of a major surf company is killed by a sniper while surfing at a company-sponsored event. The case is personal for Kono because the victim was her mentor when she surfed professionally and the chief suspect is her sharpshooter ex-boyfriend. The investigation takes Five-0 into the interconnected worlds of North Shore surfing.
Season 1, Episode 5
The two teen daughters of the U.S. ambassador to the Philippines are kidnapped. One is murdered and her body is found off the Waikiki coast. Her sister is held for ransom, but Five-0's investigation uncovers evidence that money may not be all the kidnappers are after.
Season 1, Episode 4
A convict escapes from prison and targets a young couple who won $1 million and an all-expenses paid trip to Hawaii. The probe reveals the con had help from the inside to get away and that he plans to recover money taken from a previous heist. Meanwhile, McGarrett's estranged sister visits.
A deadly gang war erupts during a high-school football game and Chin discovers that his cousin may be involved. The investigation uncovers a link between the gang and a powerful mainland mob. Meanwhile, Danny's ex-wife tries to gain full custody of their daughter.
Season 1, Episode 2
A former cyber-terrorism expert is kidnapped and Five-0 try to rescue him before there is a breach in national security. The investigation reveals the abducted man has a so-called skeleton key that allows access into government computers and that Russian mobsters are intent on obtaining it.
Season 1, Episode 1
An elite task force probes high-level crimes in this reboot of the classic series. In the opener, decorated naval officer Steve McGarrett (Alex O'Loughlin) investigates his father's murder and is persuaded by the governor to head up a new police squad that answers directly to her.