Astrid is a scientist who works for the film's primary antagonist, Angus Oldfield. Angus's goal is to breed the perfect sheep, and Dr. Rush helps him to kickstart this goal, as well as aid him in his desire to become sexually intimate with it. What he doesn't know, however, is that Astrid's ulterior motive is to use the sheep to achieve spontaneous cellular transferral.
A discarded test subject is stolen by an environmentalist named Grant, who accidentally destroys the test tube shortly after. The mutated sheep, infected with a virus, bites him and then escapes. Before long, the virus has spread to countless sheep in the area; one of whom bites Tucker, a friend of the film's hero, Henry Oldfield.
Tucker goes to Rush's laboratory looking for answers, but it incapacitated by the doctor. Astrid is fascinated to see that the cellular transferral is a success as Tucker gradually begins to mutate into a sheep. She uses an antidote to restore his human biology, and then promises to return shortly so that she can try to replicate the process. Outside, she spots that her male assistant has been gruesomely eaten by several of the sheep. She is unconcerned by this discovery, but that quickly changes once the sheep begin to go after her. She is only able to make it to a wooded area right outside the laboratory before she is then eaten alive.