Magnum is hired by a bank teller from Robin Master's bank to investigate her father, world-famous counterfeiter Herbie ""Rembrandt"" Norton, who has recently been released from penitentiary and whom she suspects has returned to counterfeiting after coming into large amounts of money since his release. Before starting investigations, the pair go to retrieve a book for Higgins from a safe deposit box at the bank, but the woman accidentally locks them in the vault, and with the time-release door and a slowly dwindling air supply, the pair are trapped inside... Meanwhile, spurred on by getting the potentially lucrative case, Thomas had promised to take Rick and T.C. for a luxurious weekend away, but unaware that Magnum is trapped in the vault at the bank, they are annoyed to presume that he has gone without them, and - with T.C. having problems with his girl-friend - they decide to hold a party at Magnum's guest house - which does not go down well with Higgins, who is holding a meditation we

Higgins is driving visiting Pamela Bates - an old editor friend of Robin Master's - along with her friend, and her secretary, to the Estate, when someone tries to run them off the road and over a cliff. But Pamela insists on waiting for her own mainland investigator friend famous crime mystery writer Jessica Fletcher.

The crossover continues on Murder, She Wrote S03E08 Magnum on Ice (II).