Daughters of Darkness (1971)

Chic lesbo vampire flick starring French legend Delphine Seyrig. A pair of newlyweds check into a Belle Epoque seaside hotel during off-season and find the only other guests at the hotel are a mysterious countess (Seyrig) and her timid secretary. As the couple get to know each other, the husband's shady past and sadistic tendencies start to bubble to the surface. They soon find the countess is getting quite chummy and might have something more in mind for them than polite conversation. This moves at a very slow pace, but in an intriguing way. It draws you in with it's languidness. This could have been an exploitation film (there are moments of cheese), but it has restraint, looks expensive, and relies heavily on Seyrig's considerable acting abilities and electrifying screen presence (her wardrobe in the film is delicious). Tony Scott's The Hunger (1983) owes this film plenty. It is ridiculously similar in style and content.