Ben voiceover.

He and Alex are in the engine trying to raise Melanie over the radio.

Flashback three months: Melanie is in the track scraper, chemically kept in temporary suspension. She revives and records a log entry. She’s just outside Casper, WY. She puts herself into suspension for another eight days.

Montage of scenes of waking and suspension. Each time, it’s harder to wake, and she despairs. At Day 172, she logs that her stimulant is gone and she doesn’t believe she can wake from suspension without it.

Layton walks Liana in the corridor to get her to sleep. Successful, he returns to his quarters and Zarah reminds him it’s time for him to get to the engine.

In the engine, he, Josie, Javi, Ben, and Alex keep a look out for visual confirmation of Melanie’s track vehicle while Ben continues to try to raise her on the radio.

Josie spots the vehicle. She, Layton, and Ben rush to bring the vehicle onboard.

Wilford watches from his window.

Till wakes up in Audrey’s arms and jumps to get ready to work. They try to establish what their relationship is.

Ben operates a crane from onboard Snowpiercer while Josie jumps out to attach the lift mechanism. A slightly conscious Melanie sees Josie through the glass hatch. The vehicle is lifted into a cold lock car.

Till brings Dr. Pelton to the cold lock and together, they transfer Melanie to the medical car.

Three days later, Melanie revives with Alex by her side. They catch up with each other.

Ben joins them and it’s a tearful reunion.

Ruth checks in on Roche with the news of Melanie being awake. She notes that tonight’s the last time they’ll pass the pyramids before reaching New Eden. Roche comments they should mark the occasion, and Ruth decides to throw a party.

Alex fills Wilford in on how Melanie survived.

Layton visits Melanie. She reveals she knows that New Eden is a lie, and asks him to get her out of the medical car.

Layton takes her to the engine. She hugs Javi and takes a seat at the controls again.

In the bunks, Melanie examines the data on the Horn of Africa. Ben comes in. She’s concerned about the plan for New Eden and decides to go talk to Wilford.

In the Night Car, LJ heads up for a walk and when Oz tries to join her, tells him he’s smothering her. He follows her to the Market where he sees Dr. Headwood hand her a small vial of something.

Layton brings Melanie to Wilford. Wilford wants her to back him in opposing the New Eden plan.

Layton and Ben talk about Melanie being back. Ben recommends Layton come clean with Josie about his feelings rather than waiting until it’s too late.

Back in the Night Car, Janitor Annie comes by looking for LJ. Oz tries to run her off but LJ comes out and hands Annie the vial Dr. Headwood gave her. Oz confronts LJ about her dealings. LJ distracts him by luring him into bed and then pulls a knife on him. Once he pleads that he loves her, she calms down, but ends on a threat.

Ruth orders all the remaining champagne brought out for the party.

Melanie and Alex get ready for the party. Melanie tries to be scientific about the Horn of Africa data. Alex believes that faith is important here.

Till finds Audrey in the Market and asks her to be her date to the big party. Audrey wants to be her date but doesn’t want to go to the party. She’s not ready to face Layton and Melanie. Till pivots and offers to take her somewhere else.

On the way to the party, Layton pulls Josie aside and declares his love for her. She admits she loves him too but right now, his duty is to the people of the train so she can’t be with him.

Melanie joins the party in the dining car. Ruth hugs her welcome.

Janitor Annie brings a trolley of desserts into Wilford’s confinement car, making sure he sees her gesture that there’s something hidden in the napkin. As she leaves, he pockets the vial.

Alex introduces Melanie to Carly.

Wilford offers to throw his guards a little party and opens up a hidden stash of alcohol and cigars.

Till brings Audrey back to the Night Car, reminding her of the good she did there before Wilford’s return.

Layton seeks out Melanie at the party. Melanie tells him New Eden is a bad idea. Layton maintains that the train is going there.

Ruth makes a speech while Wilford lights cigars for his guards and Till and Audrey dance in the Night Car.

The train passes the pyramids. Melanie leaves the party.

Oz comes to find Roche and let him know that LJ’s up to something. Before Roche can talk to Layton, Melanie makes a train-wide announcement, denouncing the New Eden plan and revealing that Layton lied to the train, telling them that he had been there.

Till leaves Audrey in the Night Car. Wilford warns his guards that they’re now at war.

Roche and the others turn on Layton.

Layton and Ben rush to the engine. Alex is in shock. Javi’s on Melanie’s side and locks Ben out of Snowpiercer.

Ben sets up in the Big Alice engine. Melanie reaches out to justify her actions but he accuses her of betraying him and killing the train’s hope. She apologizes. He hangs up.

Layton, Zarah, Till, and Josie are in Big Alice as well. Layton determines they need to figure out who is still with them now that the truth is out.

Javi informs Melanie that First is behind her and secure. Melanie goes to check on Wilford but finds the dead guards, poisoned, and no Wilford.