|Kupouli 'la (Broken)|
|Season 4, Episode 6|
|Air date||November 1, 2013|
|Written by||Sue Palmer & David Wolkove|
|Directed by||John Terlesky|
It's Halloween in Hawaii, and the team on the trail to find a doctor who's performing illegal experiments on people.
While Max is attending a Halloween party, a police officer shoots crazed doctor Michael Besner, who later infects Max. Five-0 find traces of a drug that drug cartels use to control their victims. They soon realize that Besner entered a morgue to cut off the head of a corpse, Lisa Mills, who died in a car accident. She was presumed missing a year earlier before she resurfaced; Five-0 believe that Lisa was kidnapped after finding cameras in her car and apartment.
Ultimately, it is revealed she was kidnapped by William Ellery, a scientist who believes that criminals can be reformed if their brains are infected with parasites; however, the experiments proved to have flaws, namely, that the parasites cause cysts which causes the subject to black out.
Five-0 race to save Ellery's next victim, Brock Upton. However Brock manages to break free and kill Ellery in defense.
Meanwhile, Catherine finds one of Sato's lieutenants, Hideaki Kuroda, in Hawaii.
- Max Bergman always dressed up like a Keanu Reeves characters for Halloween
- Neo from The Matrix 
- Ted "Theodore" Logan from the 1989 classic Bill & Ted's Excellent Adventure. 
- Siddhartha from 1993's Little Buddha. 
- (Wearing Red jersey with a 9) The character Jotah from the 1991, Point Break. 
- Chevalier Raphael Danceny from 1988's Dangerous Liaisons 
- 'The titular character of the film John Wick 
- It's revealed that Danny is claustrophobic.
|Alex O'Loughlin||A Navy SEAL and leader of the Hawaii Five-0 Task Force.|
|Scott Caan||2nd-in-command of the Hawaii Five-0 Task Force and Steve's partner.|
Chin Ho Kelly
|Daniel Dae Kim||A member of the Hawaii Five-0 Task Force.|
|Grace Park||Youngest member of the Hawaii Five-0 Task Force, and cousin of Chin.|
|Dr. Max Bergman||Masi Oka||Chief Medical Examiner for the Hawaii Five-0 team.|
|Catherine Rollins||Michelle Borth||An Ex-Navy Lieutenant and Steve's on-off girlfriend.|
|Sgt. Duke Lukela||Dennis Chun||Sergeant with the Honolulu Police Department.|
|Grace Williams||Teilor Grubbs||Danny Williams's daughter and first born child.|
|Sabrina Lane||Rumer Willis||Max's girlfriend.|
|Hideaki Kuroda||Brian Tee||AKA "Ryu Nabushi", he is one of Sato's Lieutenants.|
|Sergeant James Chang||Keo Woolford||A Sergeant with the Honolulu Police Department.|
|Marshall Demps||DJ Qualls||A man who appears in the episode.|
|Henry Upton||Corbin Bernsen||A man who appears in the episode.|
|Lisa Mills||Dixie Rose||A woman who died in a car accident prior to the episode.|
|Dr. William Ellery||Kenneth Matepi||The killer.|
|Moviegoer||Joseph Dubiel||A man who appears in the episode.|
|Michael Besner||Scott Folsom||A man who appears in the episode.|