Two men who lost their respective twin brothers develop a growing friendship after meeting in a support group. However, both harbor long-hidden secrets that threaten to tear them apart.

Young-goo the son of mafia boss Don Carini, is too foolish to be part of the mafia elite. One day, Young-goo comes to his father and is trained by Tony V to be his father's successor. A few days later, Young-goo accidentally rescues Nancy, the only daughter of Don Bonfante, the boss of a rival mafia family. But Vinnie, an under-boss of the Bonfante family kidnapped her and fabricates that Young-goo has taken her. Vinnie's behavior provokes an armed conflict between the two families.

In a future where a failed global-warming experiment kills off most life on the planet, a class system evolves aboard the Snowpiercer, a train that travels around the globe via a perpetual-motion engine.