Magnum is despondent over his loss of his wife Michelle, his father, Mac McReynolds and now Diane Dupres. While driving in Honolulu the next day, he sees a man who could be an identical twin for Mac McReynolds.
Robin Masters asks Magnum to track down an embezzler working in a local bank. Meanwhile, Higgins is being blackmailed and since Magnum is busy, he recruits Luther Gillis to help him find the blackmailer.
A Robin Masters' sponsored jewelry design competition is being held at the estate with over $170 million worth of jewelry on display and the insurance company sends Krista Villeroch to check on the estate's security.
Higgins' cousin Sally arrives in Hawaii to get married and Higgins has a big surprise. Meanwhile, Magnum is helping Agatha recover $10,000 from a bankrupt investment.
Someone is harassing Assistant District Attorney Carol Baldwin and Magnum agrees to help her. Higgins is facing a reunion with his old Sandhurst classmates.
Magnum and Higgins are captured along with Tyler. Rick and TC rescue Magnum and the others, and a gun fight ensues. Freedom wins and everyone returns home.