Daughters of Darkness (in France, Les Lèvres rouges, and in Belgium, Le Rouge aux lèvres, both literally translated as The Red Lips; in Dutch, Dorst Naar Bloed, meaning "Blood Thirst") is a 1971 Belgian horror film (with dialogue in English), directed by Harry Kümel. It is an erotic vampire film.
A recently married young couple, Stefan (John Karlen) and Valerie (Danielle Ouimet), are on their honeymoon. They check into a grand hotel on the Ostend seafront in Belgium, intending to catch the cross-channel ferry to England, though Stefan seems oddly unenthused at the prospect of introducing his new bride to his mother. It is off-season, so the couple are alone in the hotel. Alone, that is, until the sun sets and a mysterious Hungarian countess, Elizabeth Báthory (Delphine Seyrig) arrives in a vintage Bristol driven by her "secretary" Ilona (Andrea Rau). The middle-aged concierge at the hotel swears that he saw the Countess at the same hotel when he was a little boy. The pair may have a connection to three separate gruesome murders of young girls that occurred in Bruges the previous week. On a day trip, Stefan and Valerie witness the aftermath of a fourth. At the hotel, the countess quickly becomes obsessed with the newlyweds, and the resulting interaction of the four people leads to sadism and murder. Ilona, Stefan, then the Countess all die, leaving Valerie, now transformed into a creature similar to the Countess, stalking new victims.
Director Kumel, interviewed by Mark Gatiss for the BBC documentary Horror Europa said that he deliberately styled Delphine Seyrig's character after Marlene Dietrich and Andrea Rau's after Louise Brooks to deepen the filmic resonance of his own movie. Because the vampire character of Elizabeth Bathory is also a demagogue, Kumel dressed her in the Nazi colours of black, white and red. In commenting on both the film's mordant sense of humour, and the director's painterly eye in the composition of several scenes, Gatiss drew forth the comment from Kumel that he considers the film very Belgian, especially due to the influence of Surrealism and Expressionism.
Extensive external shooting was done at the Royal Galleries of Ostend, a seaside neoclassical arcade on the beach at Ostend (especially at the luxury Grand Hotel des Thermes, which sits atop the central section of the arcade). Interior shooting was done at the Hotel Astoria, Brussels and other exteriors at the Tropical Gardens, Meise.