Plot summary

An oil drilling company accidentally releases a prehistoric shark into a small lake. After the shark eats two police officers, and their girlfriends, as well as another officer trying to find them, Janet, a representative of the company, calls in Professor Carly Reynolds to help her kill the shark. Carly had previously witnessed her sister Rita being eaten by another prehistoric shark after it was also released into the lake years ago, although later went missing. Meanwhile, three of Carly's students, May, Kimberly, and Steven, decide to travel onto an island in the middle of the lake where Rita had been killed. They hire a fisherman named Captain Stuben to take them onto the island, although the shark soon attacks their boat, and kills Stuben, Kimberly, and Steven while May reaches shore. Carly, and Janet witness this on the lake's security footage, and Carly has Janet fly her onto the island in order to rescue May.On the island, May encounters a man named Dr. Brad Howell, who reveals that he modified the previous shark so it can fly. When Carly, and Janet arrive on the island, and reunite with May. However, they're attacked by the flying shark, and Howell holds the three hostage. It is then revealed that Howell used to work for, and was even married to Janet, although when he was fired for failing to create a genetics-altering formula for a shark, he was fired, divorced Janet, and was given the island as compensation. He then weaponized the previous shark to get his revenge. Howell then reveals that there's a boat on the other side of the island before Janet forces Carly, and May to head out to kill the shark armed with a bag of dynamite. Janet, and Howell share a kiss before they're both eaten by the shark. The shark chases Carly, and May, although they manage to kill it with a stick of dynamite before walking to the boat.