There's an unhurried calm about this movie - it doesn't feel the need to rush around in a Hollywood-style frenzy, things just gradually develop. The pace may thus seem sluggish to those used to Blade-like antics, but I like the languid grace. Newly-married but odd couple Stefan and Valerie (Quimot and Karlan - the latter would go on to Cagney and Lacey, as Mr. Lacey) find themselves sharing a Belgian seafront hotel in the middle of winter, with the Countess Bathory and her "secretary", while in a nearby town, various blood-sucked corpses are appearing.
Seyrig is fabulous as the Countess; possibly the finest female vampire ever, and she's also the most well-adjusted and pleasant personality in the film. The four characters thrash around, switching partners and you just know it's all going to end in death. Lots of death. One interesting subplot is whether Karlan's character is also a vampire: his reaction to blood is odd, he too has a same-sex "mother" lurking in the shadows, and the necessary sadistic streak is certainly present. It's another nice sidelight, to a spooky, atmospheric and effective film which has just the right mix of terror and eroticism.