When Billy Peltzer is given a strange but adorable creature called a Mogwai for Christmas, he inadvertently breaks three important rules that unleash a horde of malevolently mischievous monsters on a small town.

After surviving the Kingston Falls Incident, Billy and Kate move to New York City. When Gizmo is captured by an evil scientist in a high-tech skyscraper owned by a billionaire, a new batch of mischievous Gremlins is unleashed, causing chaos and pandemonium in the city.