Snowpiercer

A failed climate intervention has plunged the Earth into a deadly ice age, leaving the last survivors confined to a perpetually moving train that circles the globe. The passengers are rigidly divided by class, with the impoverished and oppressed tail-section dwellers surviving in squalor while the elite enjoy luxury at the front. A determined man named Curtis leads a rebellion, forcing his way carriage by carriage towards the engine, uncovering disturbing truths about the train's carefully maintained social order along the way.