Bishop and his team are drawn to investigate a massacre along the Rio Grande at the border with Mexico. What they discover is a local conflict that challenges Bishop's moral values and tests the Alliance's commitment to individual freedoms. Butter finds himself at the center of this dilemma, torn between loyalty to Bishop and to a woman who needs his help. He becomes a pawn in a political game where he is accused of murder and sentenced to death. The Alliance must find a way to save their friend without being drawn into a conflict that it cannot win.