Mr. Wilford arrives and threatens Snowpiercer, so 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.

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.