|Season 3, Episode 5|
|Air date||Monday, 5 November, 2012|
I Ka Wa Mamua
It's Halloween in Hawaii with the team investigating a grisly murder and they find themselves racing against time when evidence suggests that the killer will soon strike again.
Hawaii Five-0 investigate a road accident where the drivers of both cars have gone missing and they soon discover that the driver of one car, Lisa Heller is dead, having died as a ritualistic sacrifice.
The team soon realize that Heller attended a party in a condemned house and that the killer has taken another victim, a man named Lucas Hayes.
Research finds that the killer is Seth Tilton who is caring for his ailing grandmother Helen who is also involved in helping her grandson.
Lucas escapes from the cage, and is trying to call the police when Helen non-fatally stabs him. H50 storm the house and discover that Seth has fled with Lucas.
Helen misleads the team before she commits suicide by shooting herself with a pistol while also killing the HPD guard tasked with escorting her.
When Seth refuses to back down, Steve and Danny respond by shooting Seth dead in self-defense while also saving Lucas.
|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.|
|Kamekona||Teila Tuli||An associate of the H50 team, and owner of Wailoa Shave Ice|
|Grace Williams||Teilor Grubbs||Danny Williams's daughter and first born child.|
|Dr. Charles Fong||Brian Yang||Forensic Scientist who works for the HPD and H50.|
|Keako||Sab Shimono||Chin and Kono's uncle.|
|Seth Tilton||Chris Marquette||The killer.|
|Jesse Hills||Chris Coy||A man who appears in the episode.|
|Helen Tilton||Lee Meriwether||Seth's grandmother and his accomplice.|
|Officer Hale||Albert Ueligitone||A man who appears in the episode.|
|Lisa Heller||Stefaney Rants||The murder victim.|
|Ilani||Kristen Nemoto||A woman who appears in the episode.|
|Lucas Hayes||Jordan Matlock||A man who appears in the episode.|
|Officer Wahl||Jon Mollison||A man 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