Steve McGarrett returns home to Oahu, in order to find his father's killer. The governor offers him the chance to run his own task force (Five-0). Steve's team is joined by Chin Ho Kelly, Danny "Danno" Williams, and Kono Kalakaua.
(For Queen And Country) Five-0 must work with rogue MI-6 agent Harry Langford to find a terrorist planning to cause nuclear reactors across Europe to meltdown. Also, McGarrett and Danny ask retired FBI profiler Alicia Brown to help them find their serial killer vigilante.
(New Player) Alicia awakens in her bed to find another body with a chess piece in his mouth beside her. The team hunts for a cartel boss whose soldiers are gunning for a member of the team. Kono reconnects with Rosie.
(The Fire of Kamile Rises in Triumph) Five-0 must find McGarrett and Alicia when they are kidnapped by the serial killer they’ve been hunting,
(The Stand) When a cache of guns is stolen from a gun range, Five-0 discovers the culprit is intent on making a dramatic and potentially deadly statement on gun violence. Also, Kono and Adam are finally reunited when he is released from prison,
(House of Horrors) The murder of a medium, who was apparently scared to death by a poltergeist on Halloween, is investigated. Meanwhile, Kono and Adam are kidnapped by what appears to be a death cult.
(Mother and Son) Five-0 must free McGarrett's mother, Doris, when Catherine informs them that she was captured and is about to be executed after attempting to free Wo Fat's imprisoned father. Also, Chin loses his appeal to have Sara's adoption delayed, and she must move to Mexico.
(Rite of Passage) Danny chaperones Grace's winter formal but terrorists seize the venue and hold everyone hostage in order to kidnap a diplomat's son. Also, Danny and Grover are shocked to learn that Will is Grace's secret boyfriend.
(Two Days in November) A conspiracy theorist with compelling evidence that JFK's cabinet ordered his assassination is murdered. Five-0 investigates and delves into one of history's most fascinating unsolved mysteries.
(The Burden) Five-0 investigates the 10-year-old cold case of a missing teen when a boy suffering from PTSD undergoes hypnosis and realizes he may have witnessed her murder. Also, Danny's sister, Bridget, visits Oahu for a business conference, and he suspects that she may be getting too close to a co-worker.
(Snatchback) Five-0 races to Mexico where Chin puts his life on the line after his niece Sara is kidnapped.
(The Deal) The team handles the fallout in Mexico after Chins problems, back on the Island Grover goes undercover and things get hot.
(The Clouds Always Return to Awalua) As Max prepares to say goodbye to his Five-0 ohana, they must investigate a murder during a police convention on the Island.
(Line in the Sand) Five-0 must go up against an aggressive U.S. marshall, Lincoln, when a man wanted for murder escapes capture and seeks asylum in the sovereign land belonging to the Nation of Hawaii.
(Big Game) When working a murder case involving the illegal practice of shark finning, Five-0 uncovers the possibility that a former Nazi war criminal may be hiding out in an old leper colony in Hawaii.
(Crazy In Love) While McGarrett and Danno celebrate Valentine's Day with their girlfriends, the rest of Five-0 investigates the murder of a man taking a class on how to land women.
(Hunting Monsters) McGarrett and Five-0 once again become entangled in the twisted mind games of serial killer Dr. Madison Gray when she stumbles into HPD covered in blood that matches Alicia Brown's, and claims amnesia.
(Handle with Care) McGarrett and Danny finally track down the missing uranium, which has been used to build a bomb located in the middle of the jungle. Now, they must carefully extract the unstable explosive through treacherous terrain before it detonates.
(Exodus) McGarrett and Kono suspect that an abused young girl may be the victim of a sex trafficking ring on the Island. Also, Chin and Grover investigate a murder at a sober living facility.
(The Fishhooks of the Fishers Become Entangled) Five-0 helps PI Harry Brown work the case of a kidnapped wealthy woman whose husband may have something to hide. Also, Rachel tells Danny that she is getting a divorce from Stan.
(The Water is Dried Up) McGarrett and Five-0 are captured and face certain death after tracking a dangerous nemesis to the Island of Lanai. Also, Grover takes his son to Chicago where he testifies against a dirty cop from his past.
(Black Tears) While working the murder case of one of the last survivors of the USS Arizona, McGarrett learns about his grandfather's important role at Pearl Harbor. Also, Adam uncovers bone fragments at his new construction job and asks Jerry to help him discreetly investigate.
(Prelude) Danny protects a coma patient showing signs of waking, who was the key witness from his last HPD case before he met Steve and joined Five-0.
(A Croaking by Hina's Mudhen) When McGarrett gets a tip that someone is plotting a terrorist attack on Oahu, Five-0 searches for those behind it before it's too late. Also, Chin and Abby have a very difficult decision to make.
(The life of the land is perpetuated in righteousness) McGarrett risks his life when Five-0 attempts to rescue young girls trapped in a sex-trafficking ring. Also, Kono, deeply affected by the case, makes a life-changing decision.
(Monsters) It’s Halloween in O’ahu, and Five-0 must track down a serial killer inspired by Frankenstein. Also, Jerry calls Five-0 for help when an armed gang raids a blood bank, and Danny must track down Grace who lied and snuck out to a Halloween party.
(Day Trippers) McGarrett’s first date with Lynn (Sarah Carter) on a deserted island turns deadly when a mob boss hiding there hunts them down in order to keep his location a secret. Also, Chin, Kono and Grover must race against the game clock to locate the father of a high school football star who will be murdered by a local gambler if his son doesn’t throw the big game.
(The Artful Dodger) Five-0 must work with charming con man Hank Weber to find a killer when his female partner is murdered on the job. Also, San Francisco Police Inspector Abby Dunn comes to O’ahu and works with Chin to investigate the murders of five Chinese arms dealers.
(Charade) Five-0 goes back to school when a college professor is killed and Danny goes undercover as his replacement.
(The Sweet Science) The brother of a promising local boxer is murdered, and the chief suspect is the outspoken reigning champion opponent from the mainland.
(One's Personal Sense of Responsibility) While McGarrett and Danny attend a couples retreat in Maui to work on their partnership issues, Kamekona’s dangerous past comes back to haunt him.
(Love Gives Life Within) Aunt Deb returns to Hawaii to scatter her husband Leonard's ashes. She enlists McGarrett, Mary, and Joanie for help with a bucket list she and her departed husband intended to do together.
(Hold The Breath) While Grover travels to Chicago to finally get a confession from Clay Maxwell about killing his wife, Chin and Kono are held at gunpoint by two killers who have no idea they are cops.
(Misery Loves Company) As Five-0 investigates a double homicide involving marital infidelity, McGarrett and the team recount their disastrous Valentine’s Day experiences.
(The Good Soldier) While Danny’s mother is questioned by the FBI, McGarrett partners with a young man with autism who may have information to help solve the murder of his only friend.
(The Solid Cornerstone) When Five-0’s sketchy confidential informant is accused of murder, McGarrett asks his old friend Odell Martin to defend him.
(Assets) McGarrett and Five-0 must track down a Russian spy who has stolen a flash drive containing classified NSA information that puts the life of a member of their Ohana at risk. Also, McGarrett finally learns why Catherine left him, and Abby continues to conceal her actual mission from Chin and Five-0.
(The Hunter) When a man is found left for dead drifting off the coast of Oahu, Five-0 uncovers a deadly slave trade operating aboard an illegal fishing vessel. Also, while Danny is out with his children, his car is stolen so he commandeers a bus to chase down the thieves.
(Care For One's People) A case from 25 years ago forces Grover to take his family on the run when a dangerous mob boss tracks him down to seek revenge.
(Rampage) While Five-0 investigates the theft of a high tech, indestructible suit built for the U.S. military, Jerry helps his sister try to save a captive elephant.
(The Cost of Freedom) Five-0 goes on a manhunt when a deliberate chemical spill enables six dangerous inmates to escape, including Kono’s husband, Adam.
(For the World to Know) Five-0 tries to save a kidnapped college student from a dangerous vigilante. Meanwhile, Max, Kamekona and Flippa fight to survive after being shipwrecked.
(Blood Ties) When a woman is murdered in her home, Five-0 learns that one of their own has a deep connection to the victim’s young daughter.
(The Entrance Is Stopped with a Spider's Web) Trapped inside a dilapidated building in Oahu’s Chinatown, Five-0 must protect a wounded Gabriel and plan their escape when enemy gunmen storm the building looking to kill him and anyone who gets in their way.
(My Desire Is Only for the Chief) In order to stop a meth epidemic on the Island, McGarrett and Danny go undercover as drug pilots, but when McGarrett is seriously wounded, Danny is forced to break their cover and land the plane in order to save his partner’s life.
(Big Lie) Five-0 must interrogate members of a stunt bikers gang to find a killer who escaped by jumping his motorcycle from one roof onto another. Also, the team prepares to race in a Tough Mudder competition.
(Best Laid Plans) Five-0 investigates when a wealthy recluse is found dead in a remote field with nearly one million dollars in counterfeit bills. Also, Adam is kidnapped by the Yakuza and forced to torture one of Gabriel’s men.
(The Chilling Storm Is on the Mountains) While Five-0 investigates a scuba diver’s death from a gun recently used in another murder, McGarrett prepares to propose to Catherine.
(Do Not Disturb the Water That Is Tranquil) A murder leads Five-0 to investigate a centuries-old pirate story involving buried treasure, and it seems that the killer is using the back of a stolen painting as a treasure map. Also, the morning after their wedding, Kono and Adam (Ian Anthony Dale) are kidnapped and tortured by Gabriel (Christopher Sean), and Danny shows concern for McGarrett regarding Catherine’s return to the island.
Five-0 investigates when a bomb squad is attacked and the culprit threatens to detonate additional hidden explosive devices unless arsonist Jason Sinclair is released from prison. Also, after Adam returns from the hospital, Kono realizes that they are being watched, and McGarrett prepares to take his relationship with Catherine to the next level.
(Fire Will Never Say that It Has Had Enough) The team investigates a world class hacker who turns out to be the brother of serial hacker Ian Wright, who hacks into the Hawaii State prison and releases serial murderer/arsonist Jason DuClair. He soon begins a massive wildfire. With Kono and Chin on the mainland running their own respective task forces, McGarrett and Danny recruit lifeguard and former Police candidate Tani Rey to join the task force to help out but is reluctant to join. Meanwhile, McGarrett and Danny begin to invest in a restaurant.
(Dog Days) McGarrett and Five-0 work with an injured police dog who is the only witness to an ambushed drug bust. Also, McGarrett is visited by Junior Reigns, a former SEAL, who is looking to join the task force.
(Your Knife, My Back. My Gun, Your Head) The team enlists an old friend when a crime boss is murdered, triggering revenge killings across the island; McGarrett and Danny work out details concerning their new restaurant venture.
(No Matter How Much One Covers a Steaming Imu, The Smoke Will Rise) The lives of Five-0's informants are in danger when the HPD system is hacked and one ends up dead, forcing McGarrett to enlist the help of hacker Aaron Wright.
(At Kama'oma'o, The Land of Activities) At Halloween, Five-0 must investigate a string of murders that mirror stories from well-known Hawaiian folklore. Also, Grover is called to visit a man hours away from execution who may hold the key to a case that has plagued Grover for years.
(Unfolded By the Water Are the Faces of the Flowers) The murder of two tourists leads Five-0 to a man suffering from multiple personality disorder, where one of them becomes violent and another is a child. McGarrett is accompanied on the case by a stress management consultant, whom Danny and the others have hired to help him manage his health.
(Until We Die) On the eve of Kono’s wedding to Adam, Five-0 must stop a fanatical patriot intent on starting a new war on terror by detonating stolen nuclear warheads and framing a terrorist leader.
(Prey) While Five-0 investigates the murder of a bounty hunter after he apprehended a fugitive hiding out in Hawaii, Rachel (guest star Claire van der Boom) reveals a long-held secret to Danny that has serious ramifications. Also, as Kono’s wedding nears, Chin voices his concerns to McGarrett that Adam (guest star Ian Anthony Dale) is still working with the Yakuza.
(Sharing Traditions) When Kono goes on a solo outrigger trip around the Hawaiian islands in honor of her mother, she hits a patch of wild weather and must fight to stay alive. As Five-0 searches for Kono, they investigate a man busted for cooking meth who claims he received a threat on his son’s life if he didn’t continue making the drug.
(Chasing Yesterday) When a woman is found murdered in the hotel suite occupied by three married men, Five-0 must help the friends get over their massive hangover and retrace their steps from a wild night to find the killer. Also, Jerry witnesses a woman’s kidnapping on the streets of O’ahu.
(Fallen Star) When a performer is killed at a convention of Elvis impersonators and his body is stolen, Five-0 must track down the culprits who are after the hidden diamonds sewn into the victim’s costume. Also, Gabriel Waincroft returns to ask for Chin for help getting off the island.
(Instinct) When Grover’s oldest and closest friend tells him he witnessed his wife fall off a cliff to her death, Grover’s gut instinct tells him that this was no accident. Also, Danny and Dr. Shaw get trapped in an elevator with a dead body in need of processing
(Close Shave) McGarrett and Odell come under siege in Odell's barbershop when they try to protect a young man who is being hunted down by a gang. Also, Jerry is wrongfully accused of committing a series of home invasions.
(Justice for All) McGarrett enlists Joe's help after Danny and Chin are arrested for deadly past transgressions.
(Stakeout) McGarrett and Danny work on their relationship while they stakeout a woman's apartment after she escapes following a diamond robbery.
Five-0 enlists the help of a California ATF Agent to find a serial arsonist targeting couples on Oahu. Meanwhile, when Danny whisks Amber away for a romantic getaway, her abusive ex-husband tracks them down, intent on taking his wife back.
When a journalist is killed, Five-0 must use his past reporting to hunt down a presumed dead Congolese warlord who is alive and well living on Oahu. Also, as Valentine's Day approaches, Danny overreacts when Grace's texts to a boy start accidently coming up on his cell phone.
While Five-0 hunts for a notorious criminal who has never been seen, Kono must fight for her life when she discovers the villain's identity. Also, Kono confesses to Adam that she's conflicted about their future together because of his ties to his formerly corrupt family business.
Five-0 must find a kidnapped patient infected with a contagious and lethal strain of bird flu which the culprits intend to weaponize.
A neurosurgeon is assassinated just before performing a surgery, and the investigation also reveals the truth behind the disappearance of four reform school boys over 40 years ago. McGarrett's beloved Mercury Marquis is stolen by an unlikely culprit.
When a tourist is shot after unknowingly transporting a stolen Van Gogh, an undercover Kono and Chin enter the world of black market priceless art and are taken hostage. McGarrett asks Iron Chef Masaharu Morimoto to help train Kamekona to beat Chef Sam Choy in a shrimp cook-off.
Five-0 enlists the help of an old-school private detective to solve the murder of a young woman who was secretly working as an escort
It's Christmas in Hawaii and Five-0 travels to the Big Island, where Max is forced to work with a rival medical examiner after a cowboy is poisoned. Meanwhile, McGarrett pressures Danny into stealing a Christmas tree.
While the team investigates a couple's murder in which their sons are the prime suspects, McGarrett is shocked when Aunt Deb returns to the island with her new fiancé.
McGarrett is kidnapped by Wo Fat and witnesses what would have happened to the Five-0 team if it had taken a very different path.
The island of O'ahu goes on lockdown when Five-0 hunts a terrorist who starts using weaponized drones on civilians. McGarrett and Danno must go for a mandated Review with a psychologist, resulting in a session which looks a lot like couples therapy.
While a Navy Seal is on a secret mission, his young daughter is kidnapped. Danny must find $18.5 million in order to save his brother.
Three young women rob a tour bus, but things go horribly wrong when a man is killed and the women unknowingly steal something of great value, thereby putting their lives in danger.
When a man from Detroit is killed on the streets of Oahu, the team is shocked when they discover the killer's motives. Chin risks everything to help Danny.
On the fourth anniversary of his father's death, McGarrett meets a woman who helps him reopen the last unsolved case his dad worked on before he died.
Five-0 investigates the murder of a wedding crasher, and their prime suspect is the runaway bride. Meanwhile, Danny makes a big decision regarding his relationship with Gabby.
When Halloween comes to Hawaii and a zombie-like man is shot, Five-0 races to stop a madman who is conducting experiments on humans.
After McGarrett and Wo Fat narrowly escape from maximum security, gunmen storm Five-0 headquarters, compromising Kono and Adam's secret location in Hong Kong and forcing McGarrett to break the law and turn on his own in order to find a kidnapped Catherine.
As the Five-0 team members investigate a murder, they are led to a Texas ranger who came to Hawaii to look for his daughter; Adam and Kono fight to stay alive.
A conspiracy theorist helps Five-0 when a missing artifact is the key to solving a double murder.
As Catherine’s seemingly harmless surveillance job takes a deadly turn, Adam considers making the ultimate sacrifice to save Kono.
While working the murder case of an undercover ATF agent, McGarrett and the Five-0 team are tasked with watching Mary’s newly adopted baby after she gets sick.
McGarrett and Grover must work together to protect national security after they are tasked by the Governor to serve a warrant to a young computer hacker.
As Thanksgiving approaches, Five-0 investigates the murder of a secret service agent just as the President travels to Oahu. Also, McGarrett's Aunt Deb visits, bringing with her a shocking secret.
The attempted murder of a Pearl Harbor veteran leads Five-0 to use decades old evidence to investigate a deadly crime committed within the internment camps on Oahu during World War II.
Chin’s life is put in danger when a murder investigation reveals that the person behind the crime may be a serial killer. Meanwhile, Danny and Grace find a mysterious puzzle box washed up on the shores of Oahu.
Captain Grover is aided by McGarrett in his search for a friend who has disappeared, after it seems like he's committed murder. Kono persists in her quest to find Adam.
Internal Affairs questions Chin about his father’s murder 15 years earlier and how his then-new relationship with Malia and her family might have hurt the investigation.
McGarrett and Danny are kidnapped by an escaped convict who wants Five-0 to prove he is innocent. Meanwhile, Grace gets into trouble when she punches someone at school.
A real estate agent is found dead inside the walls of one of his listings. Meanwhile, Danny's mother makes an unexpected visit and brings with her some shocking news.
Five-0 investigates a triple homicide connected to a downed top-secret Chinese satellite, while Grover takes Danny’s mother on a ride-along.
Five-0 aims to uncovers the sordid truth when a girl is taken from her home and her father is shot in the process. Meanwhile, Danny tries to get his parents back together and Jerry deciphers a code he found on the bottom of McGarrett’s champ box.
Five-0 investigates when the daughter of a macadamia nut tycoon is murdered with a stiletto heel during Chin’s high school reunion.
Five-0 is set up when a bad tip leads them to an abandoned building that is rigged to explode with McGarrett and Danny trapped inside.
The investigation of a murdered pool cleaner leads the Five-0 team to a possible terrorist cell of radicalized students plotting an attack on U.S. soil.
McGarrett and Catherine travel overseas to Afghanistan to stop the Taliban from harming a young boy whose family saved Catherine's life years ago.
When Grover's daughter is kidnapped by an old nemesis, he is forced to help steal $100 million in order to get her back. Meanwhile, Wo Fat escapes prison and heads back to Oahu.
A double amputee goes after the police officers responsible for his injuries -- including McGarrett's father.
As the island prepares itself for the Pro Bowl, an executive from a California technology company is found dead after a tactical ops team building exercise. Unexpectedly, a star running back from the football game (Arian Foster) winds up helping Five-0 during the investigation.
While apprehending his latest fugitive, Dog the Bounty Hunter is witness to a woman falling off a balcony to her death. Five-0's trail leads them to discover that the victim lead a double life as a roller derby player. Unable to get any useful information about the victim from her teammates, Catherine is asked to go undercover as the team's jammer. Doris comes home to find a burglar robbing her stash of sensitive information.
When threats turn deadly against a tour company that endangers the local shark population, Five-0 faces the difficult task of narrowing down the suspect list. Meanwhile, the team debates whether or not Kamekona will earn his helicopter license.
McGarrett and Catherine head into North Korea to retrieve a fallen friend's body. While there, McGarrett recalls his last perilous mission in the country.
Five-0 allows a talk show host and her crew to follow them for the day, but the investigation turns dangerous when they have a run-in with Wo Fat.
When the body of a young girl who was kidnapped 10 years earlier is discovered, Five-0 must hunt down the kidnappers who have now taken their next victim. Meanwhile, Kono asks Catherine for a favor that could damage her relationship with Adam.
McGarrett must help his mother execute a covert op to retrieve an incriminating microfiche. Meanwhile, Kono’s life is in danger when she closes in on Adam’s secret.
When a plane lands on Oahu with four bodies on board and a missing terrorist detainee, the CIA tasks Five-0 with finding him before he carries out an attack on U.S. soil. Meanwhile, Kono is on the run from the police for a murder she did not commit, and McGarrett’s prison visit to Wo Fat ends with a shocking discovery.
Max and his crush (Rumer Willis) get put in harm’s way when a botched bank robbery leads the team to determine that the criminals had very unexpected motives. Meanwhile, Danny is stuck with the tough task of coming to the rescue of the most beautiful women in the world when a stalker goes after a Victoria’s Secret model.