McGarrett hires a private investigator to follow his mother. Treat Williams guest stars on Hawaii Five-O. "Kekoa (Warrior)" is the 16th episode of the show's third season.
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Hawaii Five-0 Season 3 Episode 16 Quotes

Mick Logan: You told me to keep an eye on your mother.
Steve McGarrett: An eye, not a hand, not any other body part.

Kid, you don't need a P.I., you need a therapist.

Mick Logan