Piranha. 1978.
The plot of this does sound the familiar but with a different species, government military secret of mutated piranha's that have survived the so called killing and accidentally released and go on a munch fest. Roger Corman gave us another monster movie this time with Joe Dante directing that is actually decent.
The acting is a solid, with Kevin McCarthy playing the researcher who does have a heart. Heather Menzies-Urich as the investigator hired to find two back packers and Bradford Dillman as the not so grizzly mountain man who is dragged into the mess. Barbara Steele has a small role as a military doctor and Dick Miller as a resort tourist operator who both ignore the warnings until it's too late. The effects seem outdated now as we see the piranha in the water that look like cardboard cut outs and hand puppets, enjoyable.
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