Layton uses his new position as train detective to investigate the murder while gathering intel for the revolution on the side. Meanwhile, Melanie faces a resource crisis, with potentially drastic consequences for the entire train.

Hiding out with help from his allies, Layton lays track for revolution and an engineering emergency threatens every soul on Snowpiercer.

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.

As the Big Alice crew are granted shore leave on Snowpiercer, Layton and Wilford have differing opinions on the future.

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

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

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

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

It all comes to a head as old adversaries clash, with New Eden hanging in the balance.