Laughingly billed as "the most gruesome + ghastly movie experience of the year," Horror of the Blood Monsters has the dubious distinction of being both one of the worst horror movies and one of the worst science fiction movies ever made.

By my definition, this isn't even a movie because infamously bad movie producer/director Al Adamson cobbled this schlock together from several other movies and then slapped on a few scenes of his own to try and hold it all together. A major part of this film actually comes from a horrid Filipino caveman film called Tagani, and there is a smorgasbord of standard stock footage inserted willy-nilly throughout (including a lizard fight we've all seen dozens of times in other bad movies of this era).

The film opens with five minutes of footage featuring vampires attacking innocent people, while a horrible narrator vampire describes how his all-powerful brethren trace their origins back to some gobbledygook planet millions of miles from Earth. According to him, you would have to see the original vampires (dubbed the Tubaton) back in action on their own planet in order to figure out any way of stopping them here -- and he seems a little concerned that a spaceship is currently on its way to that very solar system. With that, we're instantly transported (never to return) into a science fiction movie, with an unusually grouchy John Carradine leading a team of astronauts on a mission to explore a solar system that Dr. Rynning (Carradine) discovered himself.

Everyone in Mission Control (which consists of two people) grow concerned when communication with the ship is lost, but the ship manages to make an emergency landing on an alien planet that is remarkably Earth-like -- except for its high levels of chromatic radiation, that is. What is chromatic radiation, you ask? Basically, it's just an excuse for showing the planet-based action through a series of different color filters (thus allowing Adamson to market this as a full-color movie). Each scene looks ghastly on the screen, but Adamson apparently decided that this was the only way he knew to cover up the fact that all of the primitive caveman action on the planet was originally filmed in black and white.

I have to say that all of the seemingly endless fight scenes between warring tribes, shown in a medley of monochromatic filters, make Horror of the Blood Monsters an almost insufferable viewing experience. The horror and science fiction scenes, especially those featuring Carradine in all of his "I'm washed up as an actor and I know it" glory, may qualify as "so bad it's good," but all of the borrowed scenes from Tagani push well past the "so bad it's good" envelope. For all of these reasons and more, this film scores a perfect five stars on the bad movie meter. Don't be fooled by my rating, though (especially if you're not a connoisseur of cinematic disasters) -- Horror of the Blood Monsters is an atrociously ill-conceived and painfully horrible film.

You'll either laugh your head off or sit there stunned by the depth of this film's immense badness if you take on the challenge of suffering through it yourself. I haven't even talked about the claw-men and batboys, but I simply must mention what may be one of the most bizarre scenes I've ever seen in my life. In the midst of all of the unbridled and boring caveman warrior action, you suddenly find yourself watching the guy and girl from Mission Control having some kind of futuristic sex, which involves a lot of blinking lights and a large collection of machines that go ping -- that's all I know about, and that's all I want to know about it. This singularly weird scene provides for what just may be the ultimate WTF moment.

If you claim to be a lover of bad movies, you're pretty much going to have to watch this film at some point. After the fact, you may very well consider designing your very own "I survived Horror of the Blood Monsters" t-shirt. It definitely earns a spot on any list of the worst movies ever made.