Progeny, directed by Yuzna and co-written by Stuart Gordon, takes the alien-abduction movie and plays it as body horror about pregnancy. George designed both the alien visitors and the effects for the film’s surgical climax, and by 1998 the two of them were plainly choosing practical over digital on purpose: CG in the film is limited to environmental compositing and cleanup, while every creature close-up and the surgery itself is built, not rendered.
His alien design keeps the bulbous-headed “Grey” silhouette but adds long, jointed fingers, insect-like surfaces and a wet finish. The cesarean sequence uses a prosthetic torso on actor Jillian McWhirter: the incision opens into a physical cavity, and the extraction ends with a creature puppet. The visible effect is clear; its internal plumbing and exact materials are not documented to a crew source here.
The extracted creature is a small, wet, multi-tentacled larva with a pale translucence. No crew account identifies its materials, lighting, or operation.