Experiments turn to treachery when mad scientist Suzuki needs a test
subject for his newest serum that can radically alter humans. His chance
arrives when American reporter Larry Standford stops by for an
interview and Suzuki secretly infects the reporter. With the formula
coursing through his veins, Standford begins to feel his moods change
and in a startling scene discovers an eye growing out of his shoulder.
Another creature is literally growing inside of him, driving him to
commit a series of murders. Completely transformed into a two-headed
monster, he returns to Suzuki's laboratory. Their confrontation builds
to a fiery climax at the mouth of a volcanic inferno. Once seen, The Manster is hard to forget, containing a gruesome gallery of monsters and memorable special effects.