This strange, forgotten exploitation film has surfaced after 60 years under the title THE SEX SERUM OF DR. BLAKE. Dr. Grant (Era Dugo) returns from Africa after "risking his life" to obtain a specimen of the "serum of youth," which he describes as the "most unbelievable chemical formula ever to appear on the face of this Earth." In a lengthy flashback, while in Africa he spied on hooded, torch-bearing "African natives" in furry bikinis wandering around what looks suspiciously like the Nevada desert. These women drop trow at a stage bound altar to have group sex with a dying man before they cut out his heart.
Back in the present, Dr. Grant postulates the serum could be used as a powerful pain killer for wounded soldiers in battle, but admit an human experiment is fraught with risks. "Many men have died in the name of science," is the rationale for proceeding. Before he can find out, Grant is intercepted by spies who kill him, steal the serum, but they in turn die. Abortionist Dr. Blake (Ray Molina) just happens along the scene of the crime and takes the serum home with him and inexplicably injects himself. He visits a girlfriend and grows violent, beating her and drinking her blood. "You've got a phagocytosis of the red cells with the white cells," says another doctor, who diagnoses Dr. Blake with vampirism over the phone, and then proceeds to explain how to be a vampire without realizing he's describing a vampire. Dr. Blake kills a few more people before he is chased down by the police. Needless to say, things end badly for the doctor.
Writer-director Charles Nizet clocks a lot of time with scenes of people eating, the aforementioned African flashback, a three-way sex scene that borders on pornographic, people listening on phone calls with no cutaways and lengthy pauses, a dull boat chase, etc. In other words, despite plenty of incident the movie is drawn out and boring, as well as badly acted by a cast of non-actors.
Originally released as a sex/exploitation film in 1970, SEX SERUM OF DR. BLAKE premiered in Las Vegas, and was shown in Belgium, the U. K., and the Netherlands. A few years later, the movie was re-edited, with new scenes added, and released in the U. S. to a wider audience as VOODOO HEARTBEAT. This new version was missing much of the sexuality of the SEX SERUM cut, and was rated "R" in the US. It featured different actors and contained more explicitly horrific scenes, some of which were shot during the filming of Nizet's next movie, HELP ME, I'M POSSESSED.
