In a small town during the Christmas season, a young man named Billy Peltzer receives an unexpected gift from his father: a strange creature named Gizmo, an adorable and furry mogwai. However, this gift comes with a series of strict rules that must be followed to the letter: do not expose it to bright light, do not get it wet, and most importantly, do not feed it after midnight. Ignoring the warnings, Billy commits mistake after mistake, and gradually, his sweet pet turns into uncontrollable chaos.
When Gizmo is accidentally wet, a plague of mischievous and malevolent creatures emerges, transforming the town into a nightmare scene. The new gremlins are completely different from Gizmo: playful, mischievous, and destructive, eager to wreak havoc and terror among the townspeople. The situation becomes critical when the gremlin gang decides it's time for a party at the local movie theater, turning the cinematic experience into a complete disaster.
Billy, along with his girlfriend Kate and his friends, will have to find a way to put an end to the invasion of these creatures before they ruin Christmas for everyone. Along the way, they will face hilarious and terrifying situations, discovering that sometimes, the smallest things can bring about the greatest chaos. Will they be able to restore order and save the town before it's too late?