Plot:
With stock sea footage, the all omniscient narrator or mad scientist Dr. Zaat extols how he wants to rule the world by becoming
a shark. In his lab, he's growing some giant walking fish that hungers for human flesh. Zaat is sure he's ready and injects himself
with the formula

Why, yes, I'm doing a Dr. Herbert West, Re-Animator impression...
which turns him into the aquatic monster.

I'm not Gill Man from the Black Lagoon
Sheriff Krantz and Rex, the state inspector, have to contend with walking catfish. Rex finds a strange radiation detected
on the fish.
Zaat wants revenge on the various scientists that scorned his project years ago.

You didn't think an army of amphibious fish monsters to conquer the world was a good idea. How about now?
Yes, the mad scientist will hunt down those who doubted his genius. Zaat is moving onto his next target.
Sheriff Krantz and Rex investigate the dead scientist. Rex is told to contact INPIT, some scientific investigative agency.
Aquatic monsters also love the ladies. Zaat grabs a camping lady and takes her to his lab. However, the process kills
her.

Just be glad I've devoted my plastic surgery skills to other people...
Zaat needs a female version who will be the mother of his aquatic super-race.
That night, the INPIT agents and Rex check one of their traps and are attacked by Zaat.
The townsfolk are hounding Sheriff Krantz about the deaths.
Zaat heads into town and rampages in a drug store for some chemical.
Krantz tries to get everyone to stay inside but brings a group of hippies into the jail to keep them safe.
As INPIT gets data on Dr. Z; the sheriff has heard the stories of the strange scientist at the closed lab. As they split to
investigate, Zaat grabs agent Martha. Walker will track after them. Krantz and Rex will head straight to the lab.
Krantz fights Zaat but gets killed. Rex goes after Martha. He finds Zaat's notes and tries to rescue Martha. Rex gets
clobbered by Zaat easily. Zaat heads back to his work of a fish-woman. The mortally wounded, Rex, is able to pull Martha
out of the pool.
Zaat heads for the ocean. Walker finally reaches the lab after being bitten by a snake. He opens fire on Zaat who goes
into the ocean. Martha walks past the Walker and into the ocean.