WARNING: The following contains spoilers for "The Time of Two Engines," the Season 2 premiere of Snowpiercer.

When Season 2 of Snowpiercer begins, we find Melanie (Jennifer Connelly) outside the train smash-up that ended the first season. Wilford's Big Alice is interlocked with the Great Engine, Snowpiercer, which is now led by Layton, but Mel ends up being invited aboard Wilford's ark to meet her former boss and someone she has a deep, personal history with.

However, there's one secret she's keeping from the tyrant and other key figures that may hint at humanity's salvation in this frigid world.

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When Mel gets inside, she's shocked to see her daughter, Alexandra, alive. Alex is pissed, though, that Mel left her and her grandparents to die, but Mel admits she waited on them as long as she could before ditching Wilford too. Alex and Wilford have taken off Mel's hazmat suit and are basically keeping her prisoner, prying into how they could retake the front train, but Mel won't sell her people out.

Angered, Wilford throws Mel into lockup, but Alex seems to hold a sentimental connection to her. She's missing her mom but still has a job to do as Wilford's chief engineer. She starts making inquiries of her own, namely with respect to a vial with a snowflake she found in Mel's suit, but Mel plays it off, suggesting it's just a memento off the ground. Alex is incensed, storming off as she knows her mom is lying.

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It turns out Mel caught it from the air, which means if snow is falling from the atmosphere, there's some warming occurring. When mankind launched chemicals into the sky to stop global warming in the franchise, it froze Earth and got so cold that there couldn't even be snow as there wasn't any heat to create moisture in the air and allow snowflakes to fall. But to Mel, from the crystallization shape and pattern, this is changing. It means the world could be ready to host life and that rather than continue chugging around the world with these perpetual engines, they should stop and try to rebuild society. Sure, they'll have to bear with sub-zero temperatures for some time but life is possible again.

The problem is Mel can't let anyone know, not even Alex. Wilford has mad scientists on board his train, so she knows it's a matter of time before they make the discovery themselves and begin plotting a massacre. They have no problem with genocide if it means ensuring that there's less competition for Earth's remaining resources, so Mel's going to have be coy about how she plots out the future and their last shot at survival now that she's attached both trains permanently.

Snowpiercer stars Jennifer Connelly, Daveed Diggs, Alison Wright, Mickey Sumner, Susan Park, Iddo Goldberg, Katie McGuinness, Lena Hall, Annalise Basso, Sam Otto, Roberto Urbina, Sheila Vand and Jaylin Fletcher. The series airs on Mondays at 9pm ET/PT on TNT.

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