The creature was designed to resemble a fusion of male and female genitalia.

The plot concerns a survey team entering the abandoned Golden Spike Mine, getting sealed in by a cave-in, and discovering that something lives in the deeper tunnels.

The something is a stop-motion creature built and animated by Mark Sawicki, who plays the writer in the film narrating his story into a tape recorder. Sawicki went on to a long career in visual effects.

THE STRANGENESS (1985) was shot in 1980 and sat unreleased for five years before appearing on VHS with no theatrical run.

The cave sets were built in a California garage. The budget was $25,000. The director, credited as David Michael Hillman, was a group of USC film students led by a woman named Melanie Anne Phillips, who was not yet publicly out as transgender.

She would transition in the early 1990s, go on to work with the International Foundation for Gender Education, and in 1994 found the first online transgender support site.

The title sequence was designed by Ernest Farino, who also did the titles for The Terminator and Night of the Creeps. The synthesiser score has been compared to John Carpenter.

The film is very dark, very slow, and very cheap, and has accumulated a devoted cult following among people who find all three of those qualities interesting rather than disqualifying.