The film is set in the future (AD 2031) where, after a failed experiment to stop global warming, an ice age kills off all life on the planet except for the inhabitants of the Snowpiercer, a train that travels around the globe and is powered by a sacred perpetual-motion engine. Its inhabitants are divided by class; the lower-class passengers in one of the last cars stage an uprising, moving car by car up to the front of the train, where the oppressive rich and powerful ride.