 The FBI is called in to investigate a case of sabotage at a tungsten mine in New Mexico. The bureau is concerned because the metal is vital for U.S. defense and aerospace efforts. But the sabotage has nothing to do with the Cold War. Rather, it is the work of Tom Rule, whose son was killed at the mine and whose grandson wants to work there. Rule, believing the mine will soon close down anyway, wants to prevent his grandson from following the same path he did. What he doesn t know, and one reason the FBI is involved, is that a large deposit of tungsten is near the mine. Rhodes, investigating the case, goes down into the mine to question Rule. Meanwhile, Rule has planted a bomb. He, Rhodes and other miners are trapped in a cave-in because the mine elevator wasn t working properly. Erskine can only watch anxiously as rescuers, including Rule s grandson, try to free the entombed miners.