| La O Na Makuahine |
|Season 3, Episode 1|
|Air date||September 24, 2012|
It is also the first episode to have Michelle Borth's character of Catherine Rollins in the opening credits and as such, Borth becomes a member of the main cast and also a series regular.
While Steve struggles to digest the shocking news that his mother who supposedly died in a car bombing some twenty years ago is the mysterious Shelburne, Chin is on the warpath, seeking revenge for his wife's death, forcing the team into a final showdown against Frank Delano and Delano's own crew.
In Japan, Steve McGarrett struggles to come to terms with the revelation that Shelburne is his supposedly dead mother, Doris McGarrett with Doris revealing that she was a secret agent tasked with eliminating Wo Fat's father and that Doris subsequently faked her own death to protect her family although Steve later angrily tells his mother that Wo Fat had John McGarrett killed anyway.
As that happens, Chin attempts to save his wife, Dr. Malia Waincroft but she ultimately succumbs to her injuries and dies, leaving Chin greatly devastated.
Steve and Doris return to Hawaii with Danny Williams arriving to meet them at the airport with Danny informing them that Wo Fat has escaped and also that Malia has died.
In the morgue, the H50 team regroup and attempt to come to terms with recent events.
Fearing for his mother's safety, Steve has Doris placed under the protection of Steve's girlfriend, Catherine Rollins.
Delano and Wo Fat meet with Delano asking Wo Fat to help him smuggle drugs out of Hawaii. In exchange for that, Delano will give Wo Fat Shelburne's location.
The H50 team soon discover that Delano and his crew are posing as cleaners to help repair the damaged Honolulu Police Department Headquarters and furthermore, the group have also killed five innocent workers so that they could claim the dead men's identities and sneak into the HPD Headquarters, undetected.
Despite their best efforts, Delano's team are caught in a traffic jam just as the H50 team arrive, triggering an intense gunfight that sees Kono shoot Devon Akina, the man who dumped her into the ocean while Steve and Danny dispatch the others as Chin heads straight for Delano.
Akina uses his last breath to reveal that Wo Fat knows where Doris is before he dies seconds later.
Chin eventually catches up with Delano and consumed by revenge, Chin kills Delano in cold blood, ultimately avenging Malia.
Wo Fat escapes after Doris fires three shots.
Steve sends Doris away from the island to protect her from Wo Fat, but as her plane departs, Danny shows up and reveals that she fired the three shots into the ground, making Steve wonder why she apparently let Wo Fat escape.
|Steve McGarrett||Alex O'Loughlin||Former Navy SEAL and leader of the Hawaii Five-0 Task Force.|
|Danny Williams||Scott Caan||2nd-in-command of the Hawaii Five-0 Task Force and Steve's partner.|
|Chin Ho Kelly||Daniel Dae Kim||Former Detective for HPD and member of Hawaii Five-0 Task Force.|
|Kono Kalakaua||Grace Park||Youngest member Hawaii Five-0 Task Force and Chin's cousin.|
|Dr. Max Bergman||Masi Oka||Chief Medical Examiner for the Hawaii Five-0 team.|
|Catherine Rollins||Michelle Borth||A Navy Lieutenant and Steve McGarrett's on-off girlfriend.|
|Doris McGarrett||Christine Lahti||Former CSI agent, and Steve McGarrett's mother|
|Frank Delano||William Baldwin||A corrupt cop who wants revenge against H50. Dies after being shot dead by Chin in revenge for Delano's men killing Chin's wife, Malia.|
|Dr. Malia Waincroft||Reiko Aylesworth||Chin's wife and a doctor who dies from injuries sustained from being attacked by Frank Delano's men.|
|Wo Fat||Mark Dacascos||A crime boss targeting Shelburne who is Steve's mother, Doris.|
|Adam Noshimuri||Ian Anthony Dale||Kono Kalakaua's boyfriend and former head of the Yakuza.|
|Kamekona||Teila Tuli||An associate of the H50 team, and owner of Wailoa Shave Ice|
|Sgt. Duke Lukela||Dennis Chun||Sergeant with the Honolulu Police Department.|
|Devon Akina||Karl Herlinger||Nicknamed "Toothpick", he's the man responsible for dumping Kono into the ocean. During the gunfight, Kono fatally shoots him with Akina telling her that Wo Fat is after Shelburne- Steve's mother, Doris.|
|Sergeant Moore||Kimo Moore||A man who appears in the episode.|
|Maria Gold||Danielle Delaunay||A woman who appears in the episode.|
|La O Na Makuahine ♦ Kanalua ♦ Lana I Ka Moana ♦ Popilikia ♦ Mohai ♦ I Ka Wa Mamua ♦ Ohuna ♦ Wahine'inoloa |
♦ Ha'awe Make Loa ♦ Huaka'I Kula ♦ Kahu ♦ Kapu ♦ Olelo Ho'Opa'I Make ♦ Hana I Wa 'Ia ♦ Hookman ♦ Kekoa ♦ Pa'ani ♦ Na Ki'i ♦ Hoa Pili ♦ Olelo Pa'a ♦ Imi Loko Ka 'Uhane ♦ Ho'opio ♦ He Welo 'oihana ♦ Aloha, Malama Pono