It is about a small hospital that gets itself some big trouble. A patient who has contracted a serious case of gangrene is brought in and, unknown to the staff, the gangrene is thanks to a strange insect that used the patient to deposit eggs in. When they do find out about it, they catch it and call in an insect specialist, but, before he can arrive, the larva is accidentally mutated to an enormous size and changes into a giant insect that looks like a preying mantis. It runs loose in the hospital, killing people for it to use as hosts for its eggs, and only three brave people—a cop, a doctor, the insect specialist—are willing to stop it.
This movie is just fun to watch (especially Don Lake as the specialist, who steals ever scene he is in). A must for fans of movies like “The Thing.”