Satan's Blood  (1978)

Theatrical Release Information:
Satan's Blood

A pair of young marrieds gets caught up in the sexual gamesmanship and occult practices of a slightly older couple in this obscure Spanish horror film, which took full advantage of relaxed post-Franco censorship standards only two years after the generalissimo's death. Andres (Angel Aranda) and his pregnant wife, Anna (Sandra Alberti), live in middle-class comfort in Madrid. Out one afternoon for a walk with their beloved pooch, Blackie, they run into Bruno (Jose Guillen) and his wife, Berta (Marian Karr). Bruno claims to be an old college chum of Andres, though Andres doesn't remember him. Nonetheless, Andres and Anna agree to trek out to Bruno's countryside estate for a drink. Soon, the two couples are engaging in satanic rituals, sweat-drenched wife-swapping, and all sorts of other unsavory activities. The fun ends when Blackie turns up dead, but the unfortunate pooch is only the first of many corpses. With its S rating (for sex) and an alternate opening sequence designed to justify its exploitation elements as cautionary, Satan's Blood earned quite an underground reputation before finding new life on home video and eventually DVD. The film's Spanish title is Escalofrío. ~ Brian J. Dillard, All Movie Guide