Return of the Fly (1959) Plot Summary Explained

Philippe wants to vindicate his father, whose matter-transmission experiments were considered disastrous. After his mother Hélène dies, Philippe sees completing the work as a way to restore his family's scientific reputation and prove his father's theories were valid.

Foreshadowing: Hélène's death serves as the catalyst that drives Philippe to pursue the dangerous work.

• philippe delambre
• father
• vindication
• teleportation
• motivation

François refuses because he remembers the disastrous outcome of his brother's original experiments. He fears history will repeat itself and that the project will bring more tragedy to the family. Only when Philippe threatens to sell his share of Delambre Frère does François relent and provide the remaining funding.

Foreshadowing: François's reluctance hints at the danger that ultimately manifests when Philippe is transformed.

• francois delambre
• funding
• refusal
• family business

Alan Hinds is actually Ronald Holmes, an industrial spy hired by Philippe to help manage operations. His true purpose is to steal the teleportation technology and sell it to a shadowy buyer named Max. Holmes is using his position to gain access to the laboratory's secrets.

Foreshadowing: The timeline hints at Holmes's true allegiance when he begins plotting with Max.

• alan hinds
• ronald holmes
• industrial spy
• espionage
• max

When Holmes uses the transporter to "store" the unconscious British agent, a guinea pig had been disintegrated earlier in the same session. During rematerialization, the matter gets mixed up, the agent emerges with the guinea pig's paws while the rodent gains human hands. This demonstrates the transporter's catastrophic flaw: it cannot distinguish between different organic samples.

Foreshadowing: This disturbing result foreshadows the even more grotesque transformation Philippe will experience.

• transporter
• guinea pig
• hybrid
• mutation
• british agent

Holmes deliberately adds a fly to the transporter as a final act of sabotage before fleeing. After knocking Philippe unconscious, he traps Philippe in the device along with the fly, deliberately causing a grotesque hybrid transformation as revenge and to cover his tracks.

Foreshadowing: This malicious act directly leads to Philippe's horrific transformation into a fly-human hybrid.

• fly
• holmes
• sabotage
• malice
• transporter

When François rematerializes Philippe after Holmes traps him in the transporter with a fly, the result is catastrophic. Philippe emerges with a giant fly head, arm, and leg, while the fly gains Philippe's head, arm, and leg. The hybrid creature retains Philippe's human mind despite its monstrous body.

Foreshadowing: This transformation is the direct consequence of Holmes adding the fly to the transporter.

• philippe
• transformation
• fly
• hybrid
• mutation

Philippe, now in his grotesque hybrid form, hunts down Max first, killing him. He then waits for Holmes to arrive and kills him as well. Philippe seeks revenge against both men, Max for trying to steal his family's technology and Holmes for deliberately sabotaging the experiment and causing his transformation.

Foreshadowing: Philippe's killing spree demonstrates that despite his monstrous form, his human intelligence and desire for justice remain intact.

• philippe
• kill
• max
• holmes
• revenge

Inspector Beauchamp captures the Philippe-headed fly and places both it and the fly-headed Philippe in the transporter together. When activated for reintegration, the two beings merge back into one normal human Philippe. The transporter successfully reverses the hybrid mutation, restoring Philippe to his original form.

Foreshadowing: This final use of the transporter proves it can not only transmit matter but also reintegrate separated entities.

• philippe
• restored
• reintegration
• normal form
• transporter

Philippe's father conducted matter-transmission experiments that ended in disaster, likely resulting in death or ruin, which is why his work was considered a failure. Fifteen years later, Philippe is obsessed with proving the experiment was valid and vindicating his father's legacy, even though François and others remember the tragic consequences.

Foreshadowing: The father's failure establishes the family curse that Philippe inadvertently continues.

• father
• disastrous
• experiment
• vindication
• legacy

The transporter works by disintegrating matter and rematerializing it elsewhere, but it lacks precision when multiple organic samples are processed together. When a fly and a human are in the chamber simultaneously, the matter gets scrambled, resulting in body parts being swapped between the two beings. This fatal flaw makes the technology dangerously unpredictable.

Foreshadowing: The guinea pig/agent swap earlier demonstrates this flaw before Philippe's transformation.

• transporter
• mechanism
• flaw
• hybrid
• disintegration