Joe Dante’s solo directorial debut (he’d previously codirected 'Hollywood Boulevard') is goofy fun from start to stop, a sly 'Jaws' riff about experimental piranha developed by our government for use in Vietnamese rivers.When the killer fish are accidentally let loose in a lake near a summer camp, the carnage begins. There were a lot of Jaws ripoffs in the ‘70s, but this was Steven Spielberg’s favorite, because Dante and screenwriter John Sayles (before he started directing his own, more serious scripts) have their tongues firmly in cheek (as they did with The Howling a couple years later). It actually also works as straight horror, because it gives people another reason to stay out of the water. “Yeah, but piranha can’t survive in fresh water.” Not these suckers. They’re butt-ugly, too, and Dante has them bolting right at the camera whenever possible.Effective and enjoyable on all counts, with plenty of campy laughs and in-jokes, and a cult cast including Barbara Steele, Paul Bartel, Kevin McCarthy, Keenan Wynn, and the great Dick Miller.