This decision, however, is made difficult as two-thousand partying college students are on spring break, which is important for bringing revenue to the small town.The next morning, a lone cliff diver is attacked and consumed by the vicious, marauding piranhas.As Novak wonders aloud where the parents are, the human sized-Piranha Queen leaps out of the water and eats him.
He reunites with his old crush Kelly Driscoll and meets Derrick Jones, a sleazy pornographer, as well as Danni Arslow, one of his actresses.
Derrick convinces Jake to show him good spots on the lake for filming a pornographic movie.
Novak speculates that the rift leads to a buried prehistoric lake.
Paula and Sam scuba dive to the bottom and discover a large cavern filled with large piranha egg stocks.
Meanwhile, Danni manages to get a partially eaten Derrick back on board, where he then dies.
Deputy Fallon makes a last stand, taking a boat motor and using its propeller to shred many piranhas, though he is presumed to be killed by the Piranhas.He ties Kelly to him and lights a flare after releasing the gas from a pair of stored propane tanks.Novak starts the boat and speeds away just as the piranhas surround Kelly and Jake.That night, Jake’s mother, Sheriff Julie Forester, searches for the missing Matt Boyd with Deputy Fallon.They find his mutilated body and contemplate closing the lake.Almost everyone in the lake is either wounded, dismembered, or killed by the piranhas altogether, while the remaining surviving tourists escape. Meanwhile, Jake spots Laura and Zane on the island and forces Derrick to rescue them.