Dan Williams welcomes his Aunt Clara to Hawaii for a visit. On the flight over, she got to know Edgar Miller, an elderly man on the same flight. Once he checks into his hotel room, Miller encounters two attackers but not before he makes a telephone call to Clara. Five-O's Duke, investigating Clara's call, is initially taken in by an impostor pretending to be Miller. But Five-O, after the real Miller's body is discovered, begins an investigation. McGarrett & Co. utilize Clara as part of a con to bring the conspirators to justice.