As he continues his memoirs, Higgins recalls the spring of 1976 when a friend from Sandhurst, David Worth, arrives in Oahu to attend the funeral of a mutual friend. Insisting that his name is Sherlock Holmes, and that Higgins is Watson, David firmly believes that their friend was murdered by none other than Moriarty, Sherlock Holmes' archnemesis.

It's a case of deja vu when Magnum is reunited with an attractive woman who was his first client five years earlier. She calls for his help once more with concerns that she and her young daughter are being threatened by some surfer punks right before a North Shore surfing competition.