This atmospheric horror movie contains terrifying scenes when appears the monster and takes place the brutal killings . Based on legendary Lorelei , a known German legend dealing with a monster that has been living for centuries in a grotto beneath the river Rhein in Germany and in which rises from undersea to wreak havoc upon some beautiful Euro-babes and unfortunate victims . Plenty of lots of blood and gore , including repellent images when Lorelei removes hearts to feed herself . The fable is sometimes silly and laughable ,though the effects and action are well made . It's a slight fun with acceptable make-up , special effects , passable set decoration and functional art direction . In the film appears known Spanishtrash actresses as Helga Line , Loreta Tovar , Silvia Tortosa and uncredited Barbara Rey . Creepy and frightening musical score especially when the Lorelei appearance , being well composed by Anton Garcia Abril, author of the four eerie soundtracks of Templars living dead and composed in similar style . Colorful and evocative cinematography filmed on location in El Carcán, Madrid, Torrelodones , river Alberche, Madrid, Spain and Rhine, Germany .
The motion picture was professionally directed by Amando De Ossorio . Amando began in films as a writer and assistant director and continued his career by making short films and industrial documentaries . He was one of the main directors of the Spanish horror boom in the 70s, specially for his quartet of films about the living dead templars which started with his first great success and immensely popular ¨Tombs of the Blind dead¨ which to be continued by a trilogy : ¨Return of evil dead¨ , ¨Ship of Zombies or Blind dead 2¨ and ¨Blind dead 3 or The night of the sea gulls¨ . Amando owns his own studio and created and/or designed many of the simple special effects sequences you see in any of his many imaginative undertakings . He displayed a varied career and specialized on all kind of genres as Western in "Rebels in Canada" and "Grave of the Gunfighter" , Historical as ¨Los Cantabros¨ , Monster movie as ¨Serpent of sea¨ and , of course, Terror as ¨Malenka¨ , The possessed¨ and ¨night of witches¨ . Ossorio also studied painting and photography , moreover, he also made his living as a painter of creepy images of the Knights Templar in his later years.