It's Jimmy Buffett on Hawaii Five-0! The legendary singer is seen here as pilot Frank Bama.
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True Blood fans are familiar with Mariana Klaveno. She guest stars on the 2/7/11 episode of Hawaii Five-O.
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Hawaii Five-0 Season 1 Episode 16 Quotes

If the witness comes back this way you get her straight to the courthouse. If the shooters come back you put them down, and make sure they stay down.

McGarrett

Danno: You know what the greatest invention of all time is?
Chin: What?
Danno: The ignore button. I have a theory that whoever invented the modern cellular phone also had an ex-wife.