Michael Imperioli guest-starred twice in Season 5 as Odell Martin, a reformed ex-con and attorney who keeps tabs on the criminal underworld from his barbershop. He first appeared in "Powehiwehi" (Episode 14, Season 5) and later in "Kahania" (Episode 19, Season 5). Things got hairy during his second episode, as Martin and McGarrett were attacked trying to protect a young man who was running from the mob. He returned again the next season to help the team with his legal skills in "Ka Pohaku Kiji Pa'a" (Episode 16, Season 6).
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