A dirty cop from Danny's past comes to Hawaii to seek revenge against Danno and his family for allegedly ruining the officer's life.

McGarrett is rocked to his core when Chin Ho tells him some shocking news about Joe White. Meanwhile, Danny plays mid-wife for his ex-wife when she goes into early labor

Five-0 investigates when a teen girl is murdered by a professional hit man. Steve and his team must first determine why she was a target before they can locate her killer.

Teens discover a body in an abandoned World War II bunker. Meanwhile, Chin Ho and Malia get married.

Schoolchildren riding on a bus are kidnapped.

McGarrett goes to North Korea with Jenna Kaye (Larisa Oleynik) to deliver a ransom to rebels who are holding her fianc? hostage. Meanwhile, Five-0 investigates the murder of an investigative reporter with ties to Jenna. ...

An unidentified body is found in the trunk of a stolen car following a high-speed chase. Meanwhile, homeless Danny takes up residence on Steve's couch

Five-0 investigates a suspicious plane crash and the death of a customs agent who was on board. The case takes a twist when the probe reveals the victim was dead before the plane took flight. Meanwhile, Danny becomes the...

A young couple filming a scary documentary about a traditional Hawaiian burial site are murdered. Robert Englund guest stars

A wealthy restaurant owner is murdered and the investigation leads McGarrett to take part in a charity mixed-martial-arts fight. Meanwhile, NCIS agent Kensi Blye (Daniela Ruah) is asked to examine a video of Steve's fath...

Internal Affairs Officer Vincent Fryer interrupts Chin Ho Kelly and McGarrett as they question Kono after she's arrested for breaking the law

McGarrett and Officer Weston (Alex O'Loughlin, Lauren German) investigate the murder of a deep sea diver known for his shipwreck finds and his recent recovery of Spanish galleons

Steve investigates a Navy SEAL's murder. Meanwhile, Kono worries when Chin Ho starts hanging out with some dirty cops.

The team gets a new member

While McGarrett sits in prison awaiting trial for the murder of the governor, Danny brings him a surprise visitor to help clear him. Meanwhile, Kono is suspended for the force, pending an internal investigation

The first season concludes with criminal mastermind Wo Fat trying to destroy Five-0, after McGarrett obtains some incriminating information about the crime lord's organization.

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

The team must stop a New York detective from retaliating against a crime boss who targeted his family.

While on a hike, Danny and McGarrett find a murder victim; Chin Ho and Kono go home to visit their ailing aunt.

A science-fiction fan dressed as a superhero is murdered; McGarrett receives a visit from a CIA agent interested in finding Yakuza.

The team must stop a vengeful bomber; Danny's fun-loving brother (Dane Cook) visits unexpectedly.

Five-0 must deal with pirates who've taken a pleasure cruise full of spring breakers for ransom.

The team heads into the jungle to try to find a missing witness in a high-profile murder case before the assassins that are after her.

The head of the Tsunami Warning center disappears as the island is being evacuated for a major storm.

A high-speed police chase leaves the driver dead, but also leads to a shocking discovery. As the team is investigating this case, they find themselves needing to talk with Chin's ex-fianc?.

The Japanese mafia's possible involvement in the murder of Steve's mother surface after Mary Ann McGarrett is kidnapped and the Champ box is stolen.

The man who murdered McGarret's father resurfaces; Chin Ho's life is put in danger during a hostage situation.

The team is called in to investigate the kidnapping of a woman and the murder of a man. The wife has no memory of the events, but Dr. Bergman links the current case to several unsolved murders.

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

A security detail member is murdered before he outlines the details of an assassination plot against a ruthless dictator planning to attend an Aid Summit. Five-0 must protect the dictator while investigating the murder. ...

Danny's ex-partner in the Honolulu police department is murdered and his body found during a luau in a barbecue pit. The investigation reveals the death may be connected to corrupt cops and a powerful cocaine cartel.

A Navy SEAL accused of murder takes hostages and safe haven on a memorial battleship.

When the CEO of a successful surf company is murdered, Kono revisits her past; Five-0 is thrown into the varied but interconnected worlds of North Shore surfing.

When the daughter of the U.S. ambassador to the Philippines is found dead, the governor tasks Five-0 with finding her abducted sister.

A violent convict escapes from prison and kidnaps a young couple on vacation; McGarrett's estranged sister comes to town.

When an escalating gang war spills into the stands of the local high school football game, injuring several bystanders and killing a gang leader, Five-0 uncovers an unlikely partnership between Samoan gangs and a mainlan...

Following the abduction of a former NSA cyberterrorism expert, the team must rescue the man and prevent a breach of national security.

Steve McGarrett is summoned home to the island of Honolulu to bury his father after he is murdered by a madman. Governor Jameson wants Steve to head up a new elite police unit and she will give him full authority to get ...

Steve McGarrett is summoned home to the island of Honolulu to bury his father after he is murdered by a madman. Governor Jameson wants Steve to head up a new elite police unit and she will give him full authority to get ...