Endangered Species is a 1982 American science fiction horror film directed and co-written by Alan Rudolph, and starring Robert Urich, JoBeth Williams, Peter Coyote, and Hoyt Axton.

It follows a former New York City police officer (Urich) who relocates to a rural Colorado town, where a newly appointed sheriff (Williams) is investigating a series of bizarre cattle mutilations.

[3] Ruben Castle, a brutish and alcoholic New York City police officer, quits his job and becomes sober, allowing him to reunite with his estranged teenage daughter, Mackenzie.

Ruben encounters Harriet several times, and learns she is investigating a series of mysterious cattle mutilations, which have spurred conspiracy theories among locals ranging from UFOs to a Satanic cult in the area.

Local newspaper publisher Joe Hiatt provides Ruben background on the cattle mutilations, which have been plaguing Colorado and Wyoming, and recounts sightings of strange black helicopters flying over the region.

Ruben leaves and encounters a large grain mill truck driving erratically, leading him to follow the vehicle to a rural fenced industrial compound.

Harriet sends samples of the cattle organs to a pathologist in New York, who informs her that the tissue is riddled with the bacteria clostridium botulinum, which appears to have been modified via gene splicing.

He witnesses a black helicopter land, and a mercenary named Steele confront Ben, who has been coerced by his nephew, a Washington, D.C. politician, to allow them to use his cattle for medical experiments.

Journalists Judson Klinger and Richard Clayton Woods spent two years of researching cattle mutilations by interviewing ranchers, law enforcement officials, scientists, and other individuals who had knowledge or experience with the phenomenon across ten states, while also gathering photographs and data.

[4] Klinger and Woods employed their research in writing the film's original screenplay, which touched upon explanations ranging from Satanic cults to extraterrestrial culpability to secret bio-warfare experiments.

[5] Director Alan Rudolph and co-writer John Binder revised the screenplay, ultimately crafting an explanation commenting on abuse of power inspired by the Watergate scandal.