“It rises from 2000 miles below the earth to melt everything in its path!”
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X: The Unknown (1956) – Official Trailer, Cast & Details
X: The Unknown at a Glance
X: The Unknown is a 1956 horror, science fiction and mystery film directed by Leslie Norman, with a cast led by Dean Jagger, Leo McKern and William Lucas. It is 1 hour 21 minutes long and was released on September 21, 1956. X: The Unknown holds an average TMDB user score of 6.1/10 from 77 votes.
Watch the official X: The Unknown trailer for free in 123Movies below.
1080p HD • Free YouTube Stream
Storyline & Synopsis
Army radiation experiments awaken a subterranean monster from a fissure that feeds on energy and proceeds to terrorise a remote Scottish village. An American research scientist at a nearby nuclear plant joins with a British investigator to discover why the victims were radioactively burned and why, shortly thereafter, a series of radiation-related incidents are occurring in an ever-growing straight line away from the fissure.
Where “X: The Unknown” Fits in the 123Movies Catalog
Dean Jagger
Dr. Adam Royston
Leo McKern
Inspector McGill
William Lucas
Peter Elliott
Edward Chapman
John Elliott
John Harvey
Maj. Cartwright
Michael Ripper
Sgt. Harry Grimsdyke
Anthony Newley
LCpl. 'Spider' Webb
Ian MacNaughton
Pvt. Haggis
Peter Hammond
Lt. Bannerman
Kenneth Cope
Pvt. Lansing
Michael Brooke
Willie Harding
Frazer Hines
Ian Osborn
Frequently Asked Questions About X: The Unknown
What is the release date of X: The Unknown?
X: The Unknown was released on September 21, 1956.
How long is X: The Unknown?
X: The Unknown runs 1 hour 21 minutes (81 minutes).
Who is in the cast of X: The Unknown?
X: The Unknown stars Dean Jagger as Dr. Adam Royston, Leo McKern as Inspector McGill, William Lucas as Peter Elliott and Edward Chapman as John Elliott. The cast also includes John Harvey, Michael Ripper, Anthony Newley and Ian MacNaughton.
Who directed X: The Unknown?
X: The Unknown was directed by Leslie Norman. The screenplay is credited to Jimmy Sangster.
What kind of movie is X: The Unknown?
X: The Unknown is listed on TMDB as a mix of horror, science fiction and mystery.
What is the TMDB score of X: The Unknown?
On TMDB it has an average user score of 6.1/10 from 77 votes.
Where can I watch the X: The Unknown trailer?
You can watch the official trailer for X: The Unknown, "4K Restoration | Official Trailer", for free on this 123Movies page. It is embedded from YouTube.
What should I watch if I liked X: The Unknown?
Movies TMDB recommends alongside X: The Unknown include The Giant Behemoth (1959), The Last House (2026), Them! (1954), Underwater (2020) and The Blob (1958).
Can I stream the full movie of X: The Unknown on 123Movies?
No. 123Movies only shows official trailers and title information. Full movies are not hosted or linked on this site.
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