Valentine Pescatore is a loner with a rough past who is trying to bring some decency to his job as a US Border Patrol agent. While his boss plays sadistic games with the illegals he catches, Pescatore slips them money before turning them back. But when Pescatore chases a thug into Tijuana, he has crossed The Line. To escape prosecution, he must serve as an informant and infiltrate one of Mexicos most powerful and ruthless crime families. Soon the line between investigating the organization and becoming part of it begins to blur.