X the Unknown (1956)

"How do you kill mud?"

- Doctor Adam Royston

X the Unknown is a British science ficion/horror film directed by Leslie Norman and released in 1956. The plot revolves around an ever-growing mound of radioactive slime that crawls out of a fissure in the Scottish countryside. Filmed at Bray Studios in England, X the Unknown capitalized on the growing trend in cinema to produce creatures born of atomic mutation and science gone wrong. X the Unknown is a precursor to the campy 1958 sci-fi/horror comedy The Blob. The film was originally intended as a sequel to the popular 1955 film The Quatermass Xperiment, but screenwriter Nigel Kneale did not allow Hammer the rights to use his protagonist Bernard Quatermass.

Notes & Trivia

 * Filmed at Bray Studios in England.


 * Released in the United States in May, 1957.


 * Was included in the DVD Hammer Collection with Four Sided Triangle, distributed by Anchor Bay Entertainment.


 * Originally, X the Unknown was to be directed by Joseph Walton (real name Joseph Losey). However, actor Dean Jagger refused to work with Walton, believing him to be a communist sympathizer. Walton was eventually replaced with Leslie Norman. Illness was cited as Walton's official reason for leaving the production.


 * X the Unknown is one of the few Hammer Film Productions science fiction films that is not part of the Quatermass franchise.


 * First genre film for screenwriter Jimmy Sangster.