Shanghai in the 1920s. Ten-year-old Sam Wing, the future owner of a shop in Chinatown, meets a young mogwai named Gizmo. Determined to return Gizmo to his family and to find the legendary treasure, Sam and Gizmo, together with the street thief Elle, set out on a perilous journey across China. Along the way, they encounter a variety of monsters and spirits, while a power-hungry industrialist and his growing army of evil gremlins dog them at every turn.