The movie Return of the Fly is a sequel to the classic 1958 sci-fi horror film The Fly, which was based on a short story by George Langelaan. The original movie starred Vincent Price as the scientist Andre Delambre, whose experiment with teleportation goes horrifically wrong when a housefly enters the matter transporter with him, resulting in a grotesque hybrid of man and insect.
Return of the Fly picks up the story fifteen years later, with Andre's son Philippe (played by Brett Halsey) and his uncle Francois (played by Vincent Price in a smaller role) attempting to rebuild the teleportation device. They are aided by Alan Hindsley (David Frankham), a colleague of Andre's who hopes to profit from the invention.
Despite warnings from Francois that their experiment is too risky, Philippe proceeds with the test, promising to use only inanimate objects as test subjects. However, when a saboteur replaces one of the test objects with a living specimen, Philippe unwittingly becomes the victim of the same fate that befell his father.
Phillipe begins to exhibit strange symptoms, including increased strength, sensitivity to light, and an aversion to food. When he discovers the truth about his transformation, he becomes desperate to reverse the process, but the scheming Hindsley has other plans, using Philippe's plight for his own gain.
As Philippe's physical and mental deterioration continues, he becomes more and more like a fly, complete with wings, compound eyes, and a fly's insatiable hunger for sugar. In a climactic showdown, Philippe battles Hindsley and his henchmen while struggling to avoid being destroyed by his girlfriend's desperate attempt to save him.
Return of the Fly was directed by Edward Bernds and released in 1959. While not as well-regarded as the original, it has gained a cult following among fans of vintage sci-fi/horror cinema.