Since the title characters in Piranha are never actually seen (there’s lots of speeded-up nibbling, but no closeups of the deadly Brazilian river munchers), the pic utilizes a lot of red dye in the water, and an auditory effect for the gnawing that sounds like an air-conditioner on the fritz.
What is different about Piranha is the unusual number of victims. Not only is the requisite slew of cameo performers dispatched quickly (Keenan Wynn, Kevin McCarthy, Bruce Gordon), but an entire camp full of school children, and a holiday crowd at a lakeside resort get chomped. This is one film where the fish win.
Heather Menzies plays an aggressive femme searching for missing persons, who enlists backwoods recluse Bradford Dillman in her cause. When they stumble on mad doctor McCarthy’s mountain-top lab, they unwittingly release a generation of super-hardy piranhas McCarthy was breeding for use in the Mekong Delta during the Vietnam war.
Barbara Steele turns up as a government scientist who hints the piranhas may be back for a sequel. Menzies is attractively competent, and Dillman does what he’s supposed to, which isn’t much. One yearns to have seen more of McCarthy and his lab, where a scaly homunculus is seen lurking about, but never explained.