Mike Colby (Jesse Vint) and his robot assistant SAM-104 (Don Olivera) are sent to the planet Xarbia where a genetic research team is working on experiments to genetically synthesize a new food source to eliminate hunger. The head of the research lab is Dr. Gordon Hauser (Linden Chiles). His geneticist is Barbara Glaser (June Chadwick). In the lab they have created a synthetic DNA strain they call Proto B. There is a problem with it.

In the lab Hauser shows Colby what is left of the test animals used in their experiments. The life form they created killed all the animals and then put itself into the incubator. It then surrounded itself with a cocoon. Within the cocoon the creature, called subject 20, is mutating. The chief of bacteriology, Dr. Cal Timbergen (Fox Harris) calls it a metamorphic mutant. The creature is not only a mutation of its parent but it keeps on changing its genetic structure at fifty times the rate of any other structure. It is a genetic wildcat and totally unpredictable.

Lab technician Jimmy Swift (Michael Bowen) is assigned to clean up the lab and get rid of the dead test subjects. The cocoon starts to pulsate. Jimmy calls Hauser. Hauser isn’t really concerned but he sends Lab technician Tracy Baxter (Dawn Dunlap) to check it out. Before she gets there the creature hatches from its cocoon and attacks Jimmy. While Jimmy is being mutilated Colby meets the remaining members of the team, electrician Brian Beale (Ray Oliver) and security head Earl Richards (Scott Paulin).

As the creature grows it continues to kill. Cal learns that the people the creature attacks are dead but their bodies are still alive and changing. The mutant injects people with the Proto B/DNA strain which alters them. The procedure removes all the genetic material in the human that is different from that of the mutant. The human then becomes a pile of pure protein. The creature is turning them into a food source. Colby learns that the mutant is a combination of the organism found on the planet, Proto B, and human DNA. The mixture was then implanted into one of the researchers. Her name was Annie. The mutated organism killed her. It is now using the others on the research station as food. Since the creature is part human DNA it is technically cannibalistic. Unless they can come up with a way to stop it, subject 20 will consume everyone in the facility.

“Forbidden World” AKA “Mutant” AKA “Subject 20” was released in 1982 and was directed by Allan Holzman. It is a science fiction horror film. The film was produced by Roger Corman.

When Roger Corman is not doing his famous cut and paste routine he is recycling. Roger is nothing if not frugal. The film reuses the same film sets that James Cameron designed for Roger's “Galaxy of Terror” 1981. The effects footage used in the initial space battle is from Roger's “Battle Beyond the Stars” 1980. Director Allan Holzman maintains that just about everything in the movie was recycled from previous productions, except for the jumpsuits on the actresses. Supposedly, the mutilated animals in the laboratory were actual dead animals bought from a local pound.

The square forms lining the hallways and rooms of the research lab are both large and small hinged-lid Styrofoam boxes for carry out food and sandwiches.

Reportedly director Allan Holzman didn’t have a script when he began shooting. According to Holzman Roger’s directions were: "You have four days to write, produce and direct a seven-to eight-minute opening of a space movie… I'll give you an astronaut and a robot, and if you need any inspiration, I've always wanted to do a version of Lawrence of Arabia in outer space." What Roger ended up with was an “Alien” 1979 rip-off. Roger was OK with that after all he’s done that one before so it’s familiar territory.

The movie is not “Alien” but it is your basic Roger Corman low budget space opera with lots of blood and gore and some naked women. It’s what you expect from Roger and it’s what you get. It’s not as campy as “Battle Beyond the Stars” but it’s just as gory as “Galaxy of Terror”. True to form there are some ridiculous parts, like directing your own surgery. There are also some slow spots but the robot is cool and, if you’re interested, just wait awhile and you’ll either see a naked breast or two or you’ll see a gelatinous puddle of gore that use to be a human being.