Charlie Chan and Jimmy Chan are traveling by plane to San Francisco, setting the stage for a web of clues, color, and danger. Early on, Jimmy befriends an insurance executive named Thomas Gregory, a man who will become enmeshed in a mystery that spirals through wealth, deceit, and high-society intrigue. On board, Charlie learns that his friend Paul Essex, a writer and confidant of Norman circles, dies suddenly after receiving a radiogram warning him not to ignore the enigmatic figure known as “Zodiac.” Essex’s briefcase vanishes in the chaos, a small but telling detail that hints at a larger game.
Charlie’s path intersects with a seasoned cast of San Francisco insiders. He consults with Deputy Police Chief J.J. Kilvaine and runs into his old ally, reporter and friend Peter Lewis. A visit to the home of the enigmatic Dr. Zodiac introduces a resonance of danger and illusion: the famed local magician, Fred Rhadini, shares meals with the group and sheds light on Essex’s death, suggesting that Zodiac might be exploiting the fears of the wealthy to coerce secrets. Rhadini’s discussion of the case deepens when Essex’s death is candidly labeled a possible poisoning, though suicide cannot be ruled out.
The plot thickens as the investigation widens beyond ordinary crime. Eve Cairo, a woman connected to Dr. Zodiac, becomes a focal point of tension, particularly with Rhadini’s jealous wife, Myra Rhadini, and the socialite Bessie Sibley. The trio—Charlie, Rhadini, and Lewis—pursues leads to Zodiac's home, where they uncover a carefully curated cache of files used to intimidate and blackmail. The confrontation reveals that Zodiac’s “secrets” are built on manipulation rather than genuine supernatural power, and Zodiac’s Turkish houseman, Abdul, adds a layer of menace as he escapes with a holster that fits the weapon involved in the night’s earlier threats.
Meanwhile, Essex’s manuscript—an ostensibly fictional account of Zodiac’s blackmail scheme—serves as a road map for the investigation. Its last page, which would reveal the killer’s identity, is missing, creating tension about whose interests lie in keeping the truth buried. Thomas Gregory surfaces again in a new guise as an insurance company executive, and his presence intensifies Charlie’s suspicion that the case may involve more deception than a single crime could explain. The revelation of pseudologia fantastica—a propensity for grandiose lies—casts Zodiac in a different light, while Rhadini challenges Zodiac to a public test of psychic prowess.
A dramatic public confrontation occurs at Rhadini’s treasure-laden magic show aboard the Golden Gate International Exposition on Treasure Island. The show becomes a stage for peril as Eve Cairo makes contact with minds in the room, attempting to read the killer’s thoughts. The atmosphere grows tense when Zodiac, disguised or otherwise, appears and is invited on stage. During a levitation act, the killer uses a phantom weapon—the pygmy arrow—to strike, which leads to a shocking discovery: Zodiac is revealed to be Abdul, the houseman who orchestrated the ruse from the wings.
Yet the plot thickens further as the evidence around the murder misleads the investigators. When a brittle bow is found, it fails to account for the weapon that killed Abdul, suggesting that the true killer used another method to keep the truth concealed. Gregory’s machinations come to light again when it's revealed that he is really Stewart Salsbury, an insurance executive with a hidden agenda. Kilvaine orchestrates a controlled re-enactment of Zodiac’s murder, with Peter Lewis stepping in for the role, to tease out the killer’s method.
The tension crescendos when Rhadini’s stunning levitation trick is undone by a stabbing that targets him in the aisle. Myra, ever the schemer, uses the sphinx—an ornate, hidden-elevator apparatus—to move between backstage and dressing rooms, adding a physical dimension to the plot’s labyrinthine structure. Charlie persuades Eve to probe into the mind of the killer, and her psychic attempt reveals a chain of motivations including Stella Essex, Bessie Sibley, Thomas Gregory, Peter Lewis, Fred Rhadini, and Myra Rhadini, even though Zodiac’s own mind weaves through her readings to obscure the truth.
In a final act of misdirection, the revelation of the killer’s identity comes into sharp relief: Dr. Zodiac is Fred Rhadini himself. While all attention fixes on Eve as she reads the killer’s mind, Rhadini slips into the wings, descends below the stage via the sphinx elevator, and reemerges on stage with the intention to silence Eve. Charlie pieces together the mechanics of the crime, exposing that Rhadini used a spring-loaded wand to fire the arrow that killed Abdul, and in a final twist, Rhadini stabs himself to divert suspicion away from his own trail of deceit.
The movie closes with a measured, principled accounting of motive and opportunity, emphasizing how wealth, vanity, and a hunger for attention can drive even celebrated figures to commit elaborate frauds. The case’s most compelling feature remains the way truth slips between performances and masks, exposing how a magician—someone who shapes perception—could also manipulate fate. Through Charlie Chan’s patient, methodical approach and the ensemble’s interlocking ambitions, the mystery unravels in a way that honors both the elegance of stagecraft and the gravity of real danger.
