The Brides of Dracula

En route to taking up a position in Transylvania, French schoolteacher Marianne Danielle is abandoned at a village inn by her coach driver. Ignoring the warnings of the locals, she accepts the offer of Baroness Meinster to spend the night at her castle. The Baroness's son, Baron Meinster, is said to be insane and kept confined. After sneaking into his quarters to meet him, she is shocked to find the Baron chained up to a wall. He says that his mother has usurped his rightful lands and pleads for Marianne's help. She steals the key to his chain from the Baroness' bedroom and frees him.