Struggling actor William McFly is hired by wealthy eccentric Cecil Fox to serve as his personal secretary for a supposed "practical joke." Fox invites three former lovers to his Venetian palazzo for a final visit: Lone Star Crockett Sheridan, a Texas millionaire’s widow; Princess Dominique, a fading princess; and Merle McGill, a once-bright movie star. Accompanying Mrs. Sheridan is her nurse, Sarah Watkins. Each woman brings a valuable timepiece as a gift: Sheridan’s is an elaborate porcelain antique; Merle’s is a large quartz block with clock faces telling global time; and the princess’s gift, an heirloom hourglass, is said to be filled with precious gold powder.
McFly quickly recognizes that the setup mirrors Ben Jonson’s 17th-century play Volpone, in which a swindler feigns a dying state to dupe three men who hope to inherit his fortune, each offering luxurious gifts. A former law student, McFly begins to suspect the motives behind the "practical joke" and questions how his own role might carry legal liability.
The three women size each other up. Sheridan boldly asserts that the others might as well go home, as she is Fox’s common-law wife and stands to inherit nothing. Yet when Sarah returns from a late-night date with McFly—during which he left her alone at a restaurant for over an hour to make an important phone inquiry—she finds Sheridan dead from an overdose of sleeping pills, an apparent suicide. Police Inspector Rizzi investigates.
Sarah knows the pills were placebos—harmless fakes. McFly has already revealed to Sarah that Fox is orchestrating the charade, and that the final joke is the reading of the will, empowering McFly to choose the heir. Proof positive are several quarters from Sheridan’s missing roll of change that Sarah found in McFly’s room, though she suspects McFly’s innocence and Fox’s guilt. When Sarah confronts McFly, he locks her in her room, claiming it is for her own safety. She escapes via a dumbwaiter and warns Fox that she has confronted McFly. However, Fox’s displeased reaction puzzles her, and he sends her back to her room.
The next morning, Fox is found dead. McFly reveals that Fox killed Sheridan. The quarters Sarah found had been taken by Fox—who, driven by greed, had even used petty change—and had been lost to McFly during a poker game. Despite the elegance of his palazzo, Fox was financially ruined. As Sheridan’s common-law husband, Fox had plotted to inherit her enormous fortune. Once McFly had uncovered the truth (and told Sarah), Fox realized he would be arrested for Sheridan’s murder and chose suicide. In a final disdainful act, Fox had shattered the timepieces given to the women. The princess’s hourglass is found empty of its gold dust. Fox had emptied the interiors of all the chocolates, filling them with the gold dust and swallowing the hourglass’s entire contents. The contents, it turns out, were pyrite—fool’s gold. Unheard by the cast, Fox’s spirit lingers as a voiceover, resentful that the princess has cheapened his parting gesture.
The heiress plan unfolds as Sarah whimsically asks McFly to write her name in Fox’s will as the heir to the “worthless” estate, with Inspector Rizzi signing as a witness. After McFly complies, Rizzi compliments him on his “generosity”—while Fox may have been deeply in debt, Sheridan’s vast estate ensures that Sarah will emerge as an incredibly wealthy woman. Sarah then reveals that she intends to marry McFly once he resumes his law studies. Fox’s spirit closes the tale with a defiant, approving nod, acknowledging the clever outcome and the enduring irony of his own scheme.
