根据多个真实矿工场爆炸事件改编，讲述位于阿帕拉契山脉中地下两英里的矿工场，被困的九位矿工仅有一小时含氧量的氧气瓶，他们该如何逃出生天？

The expanded third season picks up six months after the events of season two and follows Lt. Joe Leaphorn and Jim Chee as they investigate the disappearance of two boys, with only an abandoned bicycle and blood-stained patch of ground left in their wake. Meanwhile, Bernadette Manuelito attempts to settle into her new life 500 miles from home with the Border Patrol, but stumbles across a conspiracy involving human and drug smuggling with far-reaching implications.