Piranha (1978)

“The deadliest maneaters of all!” insists the trailer for this 1978 grindhouse classic, another Jaws knockoff that went small, figuring that audiences — especially those who don’t live near an ocean — might be scared of hundreds of sharp-toothed little fish that turn “quiet streams into rivers of living death!”

Laugh if you like, but some very talented people came out of the Piranha franchise: Executive produced by Roger Corman, it was directed by futute Gremlins mastermind Joe Dante, and co-written by acclaimed filmmaker John Sayles. Piranha II: The Spawning, was directed by James Cameron.