Directed by Luigi Batzella (Nude for Satan 1974) this was Rosalba's last gothic horror role and features some very nice cinematography by future cannibal/ horror/sleaze & Emanuelle expert Joe D'Amato. Co-starring Mark Damon who plays twin brothers, one of whom travels to the Transylvania village of Ladracu (dig that mixed up spelling !) to locate the Ring of Nibelung. After arriving he finds a countess (Rosalba) living in Castle Dracula who has the ring and uses it to summon the local virgins (all of whom wear see-thru nighties) to her black magic rites. Damon is soon seduced and possessed by the evil countess, which in turns leads the other twin to investigate the weirdness.
Somewhat ludicrous plot is helped by good performances by the leads, some fairly impressive production design and the above mentioned work of D'Amato and director Batzella. Rosalba has three (!) major nude scenes and even gets to turn into a giant bat. Her rising blood covered out of the tomb is one of the highlights of Italian horror cinema (probably any type of cinema for that matter).