A CEO is killed on this episode, and the investigation forces Kono to revisit her past. Get an idea of what we mean via the official promo for "Ko'olauloa."
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Hawaii Five-0 Season 1 Episode 6 Quotes

Carlton Bass: He marketed the Northshore surf lifestyle and made a lot of money. A lot of people resented that.
Kono: Only one pulled the trigger.

Danny: I hate it when rich people get killed.
Steve: Why?
Danny: They have something everybody wants.
Chin Ho: Which means plenty of suspects.