At the end of Season 1, the survivors of the revolution are trying to pick up the pieces and maintain a fragile peace amongst the now merged classes with Layton (Daveed Diggs) emerging as the train's leader. Discovering Mr. Wilford (Sean Bean) is alive and headed their way on a rival train, Melanie (Jennifer Connelly) risks going outside to prevent him from invading Snowpiercer. While she's out there, it's revealed that Alexandra (Rowan Blanchard), Melanie's daughter, who she thought had died, is alive and has become Wilford's dedicated protegee. In season two, an entirely new power struggle emerges, causing a dangerous rift as people are divided between their loyalty to Layton and to Mr. Wilford, who has a new train, new technology and a game plan that keeps everyone guessing. While Layton battles Wilford for the soul of Snowpiercer, Melanie leads the charge on a shocking new discovery that could change the fate of humanity.

Mr. Wilford has arrived. And as this new threat rattles Snowpiercer to its core, Melanie makes a move that can't be undone.

An exchange is made between the two trains, but a far greater revelation might be just over the horizon.

Melanie embarks on her most dangerous mission yet, while Layton reckons with his personal choices.

The Big Alice crew is granted shore leave on Snowpiercer; Layton and Wilford disagree.

Layton and Miss Audrey make a risky play for Big Alice, but Wilford has his own plans.

Mel arrives at the research station, where she makes some startling discoveries while struggling to survive and thinking back to the days before the Freeze.

Layton and Till investigate the murders. Wilford leads Miss Audrey down a dark path.

An engineering catastrophe forces Layton to make a difficult choice that might cost him everything.

Wilford assumes control of Snowpiercer; those who are close with Layton grow anxious to learn their fates; Josie tests her newfound ability.

As the train approaches Melanie's retrieval point, Layton leads a furious attempt to try and pick her up but not without some sacrifices.