720p Web-dl: Snowpiercer S01e03

Layton stares in horror. The message is clear: the train’s power structure will never allow a Tailie to expose their secrets.

Layton’s investigation leads him to a secret meeting in the Night Car (the train’s velvet-draped, hedonistic club run by the enigmatic Miss Audrey ). There, he learns that Sean was part of a quiet resistance—not the violent Tailies, but Third Class citizens tired of being one step from the tail. They want access to the front, not revolution. Layton realizes the killer is likely someone inside the train's security apparatus.

The episode’s title becomes clear: physical access cards are the only currency that matters. Layton discovers that Sean’s murder wasn't random. Sean was a "Jackknife"—a smuggler who helped people move between classes. He had been stealing access keys to the mysterious "Drawers" (a hidden cryo-section of the train).

Layton has been promoted to Detective —a title with no real power. He is given a small closet to sleep in near Third Class, a token uniform, and a permanent escort, Osweiller (a brutal, loyal "Brakeman"). Layton isn't solving the murder of Sean (the tailor) to find justice; he's a pawn in a larger game.