http://en.wikipedia.org/wiki/Incubus_(1965_film)
Incubus (Esperanto: Inkubo) is a 1965 black-and-white American horror film, restored in 2001. Incubus was directed by Leslie Stevens, creator of The Outer Limits, and stars William Shatner, shortly before he would begin his work on Star Trek... The film was performed entirely in the constructed language Esperanto. This was done to create an eerie, other-worldly feeling, and the director has prohibited dubbing into other languages.
