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 it seems that it's not a case for Thomas, when Pamela insists on waiting for her own mainland investigator friend to arrive and look into it - much to the annoyance of Thomas, who is supposed to be busy entering into a hotel land buying venture with Rick and T.C., but can't help himself investigating the case none-the-less. Pamela's investigator friend turns out to be famous crime mystery writer Jessica Fletcher, and so both Jessica and Magnum set about investigating just who wants one of the visiting guests dead, and why... (thetvdb.com)