P.I. Gideon "Bud" Lowry has been known to play Cole Porter tunes during his late-night piano gigs, but lately he's had reason to finger some melancholy melodies. Besides a suspicious fire near his Duval Street home, Gideon's old flame, successful restaurateur Gabriella Wade, is getting married. Years ago, Gideon and Gaby were a hot item, before her true love -- her Blue Moon restaurant -- monopolized her time. But now her wheeler-dealer fiance, Roy Emerson, is refusing to take a simple medical test and she wants Gideon to find out why.
Fired up by his misfortunes and a strong desire to protect Gaby, Gideon begins an investigation into Roy's background that stretches from Key West to the Wild West -- Wyoming. And the results are explosive. But before Gideon can open Gaby's love-blind eyes, she and Roy elope, and disappear. With throngs of tourists descending upon Key West for the annual Halloween parade, Gideon is one native Conch who isn't masking his fears -- because if he doens't find Gaby soon, he'll be left standing alone at the Blue Moon forever.