After hippies attack a boy's family, he takes extreme measures for revenge: serving meat pies filled with rabies to the drugged-out cult. Soon, the flower children are foaming at the mouth and attacking everyone in sight. I DRINK YOUR BLOOD became a grindhouse smash upon its release in 1971, thanks in no small part to its being the first film rated X for graphic violence. Bill Landis, writing for his 42nd St. fanbook Sleazoid Express, praised it as "a post-Manson variant on NIGHT OF THE LIVING DEAD," that represents "the pinnacle of the blood horror movie."