When the body of the night watchman from the Metropolis Munitions Plant is found dead in a swamp, a ring of saboteurs is believed to be responsible. Lois heads off to the plant in search of a story and takes on a job as a plant worker. While undercover, Lois is caught by the saboteurs as she is spying on them and they force her into a torpedo in a bid to dispose of her before they act on their plans to destroy the plant.