Ganja & Hess (1973)

When two prominent black anthropologists, Dr. Green and Dr. Matara, uncover the remains of an ancient African tribe of bloodsuckers called the Myrthians they unleash an evil force buried for centuries beneath the earth. Matara, possessed by the spirit of the Myrthian queen, attacks his partner and then kills himself- leaving Hess to return to the U.S. with an unquenchable thirst for blood. After seducing Matara's widow, Green soon has her hooked on the red stuff as well. Together they lure innocent victims into their deadly trap, leaving a trail of drained bodies in their wake. The grisly murders go unsolved-that is, until the fateful day when Green stumbles into a Gospel meeting and all hell breaks loose.