In the midst of a hot summer, a tranquil lake in Arizona becomes the perfect setting for the dream party. Thousands of young people decide to enjoy their vacation by the beach, oblivious to the danger lurking beneath the surface. Meanwhile, after an earthquake at the bottom of the lake, an ancient and voracious group of prehistoric piranhas are awakened from their slumber, hungrier than ever.
The story follows a cast of rather colorful characters: from the intrepid sheriff trying to maintain order to a brave young woman willing to protect her friends. As the party progresses, the festive atmosphere turns terrifying when attendees start to disappear into the water, attacked by these ferocious creatures. In a blend of dark humor and horror, the characters must come together to survive the massacre that unfolds, while battling their own personal demons and desires for fun.
With explosive scenes and a breakneck pace, the situation quickly escalates, pushing the tension to the limit and keeping the audience on the edge of their seats. The battle for survival becomes a desperate struggle, where cunning and courage are the last hope against one of the most lethal threats of the aquatic world. After the last drop of blood is shed, only the cleverest will emerge alive from this watery nightmare.