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The Keep is a 1983 science fiction and fantasy horror film directed by Michael Mann and starring an ensemble of actors lead by Scott Glenn, Gabriel Byrne, Jürgen Prochnow, Alberta Watson and Ian McKellen.
Set in an ancient fortress in Romania during WWII, the film deals with a group of German Wehrmacht soldiers who make a terrifying and deadly discovery inside the old keep.
It was produced and released by Paramount Pictures. The story is based on the F. Paul Wilson novel of the same name, published in 1981 (1982 in the United Kingdom).
Because of studio medling and interference the production of the film was very troubled and the final movie was both a critical and comercial failure.
However, due to some very awesome imagery and cinematography, haunting visuals as well as an epic and enigmatic ethereal score -composed mostly of moody soundscapes- by German Electronic band Tangerine Dream , it has achieved cult status and has become a very popular rare obscure film over the years.