Cullen's past comes back to haunt him and may affect the future of the railroad on Hell on Wheels. "The Railroad Job" is the fifth episode of the show's second season.
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Hell on Wheels Season 2 Episode 5 Quotes

Let's do it.

Cullen Bohannon

To Mr. Bohannon. He may be a son of a bitch, but he's our son of a bitch.

Mr. Toole