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.
The best episode of "Hawaii Five-0" season 9 is "Ka 'owili 'oka'i (Cocoon)", rated 7.7/10 from 493 user votes. It was directed by Bryan Spicer and written by Peter M. Lenkov, Leonard Freeman. "Ka 'owili 'oka'i (Cocoon)" aired on 9/28/2018 and is rated 0.0 point(s) higher than the second highest rated, "Ke Kanaka I Ha'ule Mai Ka Lewa Mai (The Man Who Fell From the Sky)".
After Steve’s CIA agent friend is killed, McGarrett lets himself be captured by the group he thinks is responsible and endures a torturous sensory deprivation tank to find the killer. Also, Tani wrestles with whether or not she will tell McGarrett about the murder weapon she found at Adam’s house.
Director: Bryan Spicer
Writer: Peter M. Lenkov, Leonard Freeman
When a vacationing dad on a flight to Honolulu is kidnapped and force to parachute mid-flight, Danny, Tani and Junior track him through the jungle to discover that he may not be who he seems. Also, McGarrett is threatened with a secret from his past.
Director: Eagle Egilsson
Writer: David Wolkove, Matt JL Wheeler
Crime spikes when a heat wave hits Oahu, causing McGarrett and Danny to hunt down a bank thief, and Tani and Junior's car is stolen while they're on duty. Also, Grover plays the golf game of a lifetime, and Kamekona incites a riot by price-gouging on his shave ice.
Director: Antonio Negret
Writer: Rob Hanning
Jerry accompanies Junior as he escorts a fallen soldier home to Oahu. Also, McGarrett and Danny discover a dead body when they delve into the illegal and highly profitable black market for sand.
Director: Ron Underwood
Writer: Talia Gonzalez, Bisanne Masoud
On Halloween, Jerry and his friends search his childhood camp for evidence to a murder he witnessed as a boy, while McGarrett investigates a little girl who drew pictures depicting the scene of a recent murder before it was discovered.
Director: Elizabeth Allen Rosenbaum
Writer: Zoe Robyn, Sean O'Reilly
McGarrett crosses the line and is arrested while investigating the death of his former SEAL buddy, who died while making an emergency landing on an aircraft carrier, and the only survivor is a baby. Also, Adam returns to Oahu with some devastating news about his marriage.
Director: Peter Weller
Writer: Rob Hanning, Paul Grellong
McGarrett investigates a cold case from the 1940s, one that his grandfather and the famous Honolulu detective Chang Apana worked on, and he tries to deduce how the case could have been solved. Also, McGarrett and Danny get ready for the opening of their restaurant.
Director: Bryan Spicer
Writer: David Wolkove, Matt JL Wheeler
Thanksgiving brings Grover’s parents and brother Percy Jr. to Oahu for a visit tainted by sibling rivalry, and Five-0 investigates a thief who is crushed to death by an empty safe.
Director: Carlos Bernard
Writer: Chi McBride
A renowned urban vigilante is killed after making another citizen’s arrest, and Five-0 delves into the world of super heroes and comic books to find the killer. Also, Adam finally gets closer to finding out who killed his sister.
Director: Brad Tanenbaum
Writer: Christos N. Gage, Ruth Fletcher
After fighting off an assassin in his own home, McGarrett and Joe White flee to Montana to prepare for a battle against those exacting revenge for a past SEAL mission.
Director: Gabriel Beristain
Writer: Paul Grellong
Steve and Catherine are still reeling from the murder of one of their ohana and, along with Danny, Junior and some old friends, Harry Langford and Wade Gutches, hunt down the killer. Also, Tani and Grover investigate when a bag of human bones, discovered inside an abandoned storage locker, goes missing.
Director: Carl Weathers
Writer: David Wolkove, Matt JL Wheeler
MacGarrett and Five-0 support Danny and Rachel by determining what happened when gets into a life-threatening car accident and lands in critical condition. Also, Tani helps Koa when his rehab patient goes missing.
Director: Roderick Davis
Writer: Zoe Robyn
Adam, Junior and Tani travel to the bottom of the Pacific Ocean when a murder takes place in a remote underwater lab, and the killer may still be on board
Director: Karen Gaviola
Writer: Rob Hanning, Sean O'Reilly
While investigating Flippa’s friend’s murder, McGarrett and Grover uncover a deadly plan by an extremist group on the Island. Also, Grover has an emotional reaction to the case.
Director: Peter Weller
Writer: Paul Grellong
As a dangerous hurricane hits Oahu, Five-0 is tasked with protecting El Diablo, a captured serial killer who is being hunted by an assassin. Also, Tani's civilian safety check during the storm turns deadly and Rachel and Charlie evacuate to Danny's house, where the ex-spouses reminisce.
Director: Karen Gaviola
Writer: Rob Hanning
When the top salesperson for a beauty company/pyramid scheme is murdered, Five-0 sifts through a long list of possible suspects who would want her dead. Also, Adam befriends a homeless man estranged from his family.
Director: Jerry Levine
Writer: Talia Gonzalez, Bisanne Masoud
Junior is torn between his duties as a member of Five-0 and his feelings for his former girlfriend when her new love, the father of her son, is one of the culprits in a bank-heist-turned-homicide.
Director: Alex O'Loughlin
Writer: David Wolkove, Matt JL Wheeler
Tani and Junior go undercover at a gym to track down a deadly batch of steroids that’s killing users, before the drugs claim any more victims. Also, Danny and MacGarrett sub as bodyguards for Danny’s high maintenance ex-mother-in-law, Amanda Savage, a wildly famous romance novelist with whom he has never gotten along.
Director: Eagle Egilsson
Writer: David Wolkove, Matt JL Wheeler
Five-0 investigate the murder of a window washer and find that the victim is actually a renowned street artist who may have a politically motivated bounty on his head. Also, Grover and Adam look into the murder of a gambler, and Junior helps his father when they are reminded of his sister’s death.
Director: Maja Vrvilo
Writer: Christos N. Gage, Ruth Fletcher
Five-0 must locate a teen girl who purchased a gun from a junkie, and discover that the firearm, over the course of decades, has affected all of their lives.
Director: David Straiton
Writer: Paul Grellong
Five-0 investigates the murder of a man whose body may hold the key to a 20-year-old case involving a kidnapped girl whose father never stopped looking for her.
Director: Jerry Levine
Writer: David Wolkove, Matt JL Wheeler
While Adam investigates the murder of an undercover FBI agent about to wed the daughter of a Yakuza leader, Noelani is held hostage and forced, along with her mentor Dr. Chu, to operate at gunpoint on a criminal.
Director: Brad Turner
Writer: Rob Hanning, Ashley Dizon
While McGarrett helps his visiting sister, Mary, spy on her shady neighbors, Five-0 investigates the murders of a ride-share driver and his passenger. Also, the team teases the youngest members of Five-0 when Junior escorts Tani to a wedding.
Director: Gabriel Beristain
Writer: Zoe Robyn
Fugitive hacker Aaron Wright resurfaces to ask Five-0 for help when his co-workers at the NSA, which he has been working for, are all murdered. Also, Junior speaks at the parole hearing of the drunk driver who killed his sister.
Director: Peter Weller
Writer: Sean O'Reilly, Paul Grellong
Five-0 continues to hunt down escaped criminal Aaron Wright before he can sell cyber-weapons to the highest bidder. Also, the lives of McGarrett and the team are put in danger when a visitor comes to headquarters to make amends.
Director: Eagle Egilsson
Writer: David Wolkove, Matt JL Wheeler