Steve McGarrett is summoned home to 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 the job done. Initially he turns down the job, but when he meets the man charged with investigating his fathers' murder, he changes his mind so he can find his fathers' killer himself.

When a former cyber terrorism expert is kidnapped, Five-0 is assigned to find the missing expert in order to protect national security.

Five-0 discovers a connection between Samoan gangs and a mainland mob after an escalating gang war wreaks havoc during a local high school football game.

Five-0 is called in to locate a dangerous escaped prisoner and to find him they need to determine his reasons for escaping. Steve's sister, Mary Ann arrives from the mainland for a visit and brings trouble of her own.

When a young teenage girl's body is found near Waikiki, Steve and the team are assigned to finding her missing sister. The case is further complicated since their father is Michael Reeves an United States Ambassador assigned to the Philippines and friends with the Governor.

Five-0 delves into the worlds of North Shore surfing when the CEO of a successful surf company is murdered.

McGarrett must rely on his SEAL skills to diffuse a hostage situation. A Navy SEAL on the run for murder takes hostages and refuge aboard the U.S.S. Missouri Memorial Battleship.

The team is up against Internal Affairs, dirty cops and a powerful cocaine cartel when they investigate the murder of Danny's ex-partner found dead at a Hawaiian luau with his badge in his mouth.

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.

The only lead in a case forces Danny to ask his ex-wife for help when a ring of thieves targets an armored car, killing the security guards but not taking any of the money.

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.

Victor Hesse returns to Hawaii and Steve discovers that he has another connection to the island through a local criminal. Chin finds himself the victim of Victor's games when he is taken hostage and has a bomb strapped to him.

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.

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-fiancé.

Five-0 must find the missing head of the Tsunami Warning Center just as the island is about to be assaulted by a major tsunami.

When the sole witness in a high-profile murder case disappears, Five-0 must head into the jungle to locate and protect her from assassins who are closing in fast.

The team must deal with pirates who've taken a pleasure cruise full of spring breakers for ransom, as well as their worried parents.

When a Judge's daughter is murdered, the team must figure out why, before more killing occurs. Danny's brother Matt is in town but a family reunion is not the reason.

Five-0 combs a convention to find the killer of a sci-fi fan who was thrown out of a high-rise window. A CIA agent who's interested in the Yakuza that killed McGarrett's parents shows up in town to meet with Steve.

Steve and Danny stumble upon a homicide case while out searching in the jungle for Hawaiian petroglyphs. While on a visit with Chin Ho to visit their dying aunt, Kono learns what really happened to end Chin Ho's career with the Honolulu police.

Five-0 must intervene when a NYPD detective goes seeking revenge against a local crime lord.

A renowned photographer has been murdered and Danny thinks this case may be the best one yet when he has to talk with the models in town for a sports magazine's annual swimsuit cover shoot.

Agent Kaye's information has helped Five-0 narrow in on capturing Wo-Fat, but before they can act Danny becomes exposed to a lethal chemical. The investigation into this neurological agent takes precedence as Five-0 must prevent a bio-terrorism threat to the island.

As McGarrett and his team close in, criminal mastermind Wo Fat retaliates against Five-0. And without the Governor backing them up, McGarrett's showdown with Wo Fat could mean the end of Five-0.