For generations, all that distinguished Eagle Pass, TX, from Piedras Negras, MX, was the Rio Grande. But when darkness descends upon these harmonious border towns, a cowboy and lawman face a new reality that threatens their way of life. 　　 　　 　　译文(3): 几代人以来，得克萨斯州的伊格尔山口与墨西哥的皮德拉斯·内格拉斯唯一的区别就是格兰德河。但是，当黑暗降临在这些和谐的边境城镇时，牛仔和执法人员面临着威胁他们生活方式的新现实。