Lost on the way to their honeymoon, a young couple stumbles upon a mysterious family of vampires and their unspeakable evil leader. A wrong turn leaves Marianne (Jennifer Daniel) and Gerald (Edward De Souza) stranded in a remote Bavarian forest where they have no choice but to accept the hospitality of the hypnotic Dr. Ravna (Noel Willman), distinguished lord of the local castle. Ravna uses his "children" to lure the newlyweds to his liar, and soon, they are plunged into a nightmare of horror and deception from which there may be no escape. Their only hope is Professor Zimmer (Clifford Evans), who calls upon an ancient ritual in a desperate attempt to destroy the vampires and free Marianne from Ravna's power. A lush 19th century setting, masterful direction, and vivid special effects intensify this spooky Hammer Films chiller.