Piranhas

Scientists developed a variety of piranha which can live in fresh and salt water. Then the government project closed down, and they poisoned the water. But the fish survived, and eat Keenan Wynn.

It's a dumb-sounding idea for a film, one of the many movies that came out after the success of JAWS. Surprisingly, it's a funny spoof of the movie, from the posters based on the mega-hit's poster, to director Joe Dante having two-legged reptiles running around, to a silly pastiche of the beach scene. Writer John Sayles was so disgusted that he thought about giving up on film, returning to novels Instead, he took his earnings and made RETURN OF THE SECAUCUS SEVEN, and Steven Spielberg thought it was so funny, you talked Universal out of a lawsuit and hired Dante.