• Non Sequitur Scene: The entire hippie scene.
  • Fridge Logic: How exactly did Leopold, implied in one scene as being as an ex-Nazi scientist and quite possibly a wanted war criminal, manage to set up shop in Florida under his own name?
  • Narm: The entire opening speech is completely ridiculous, but clearly intended to sound sinister and foreboding. Maybe if the guy wasn't talking about "sarcasm fish" and how he loves them...

"...and at just the right moment...ATTACK!"

    • The brainless government officials, who initially call the bites that of a cat (?) or an ape (?!).
  • Special Effect Failure: Unless ol' Doc's monster form is supposed to make us laugh, it falls neatly into this category. He looks like Trumpy's reclusive uncle or something.
    • RedLetterMedia accuses George Lucas of ripping off Greedo from the film. (Despite being filmed in 1971, it wasn't released til 1980, however.)
  • What an Idiot!: A defining moment of Walter's stupidity; taking a dune buggy into a swamp where it can be stalled instead of following the other characters on the dry roads to the villain's lair.
    • To be fair, at this point the characters weren't 100% sure that Leopold and the fish monster were one and the same. Walter tracks the radioactive trail of the monster while the others go right to Leopold's hideout to confirm that the two are the same person by ending up at the same place, or he was hoping to head the monster off at the pass.
    • Of course, the sheriff tops this by forgetting he has a gun.
    • "A giant walking catfish is killing people? Well, it probably doesn't have anything to do with that super-creepy scientist who wanted to turn men into fish."