Sixth Column

by Robert A. Heinlein

A top secret research facility hidden in the Colorado mountains is the last remaining outpost of the United States Army after its defeat by the PanAsians. The conquerors had absorbed the Soviets after being attacked by them and had then gone on to absorb India as well. The invaders are depicted as ruthless and cruel—for example, they crush an abortive rebellion by killing 150,000 American civilians as punishment. Noting that the invaders have allowed the free practice of religion (the better to pacify their slaves), the Americans set up a church of their own in order to build a resistance movement—the Sixth Column (as opposed to a traitorous fifth column).

The laboratory is in turmoil as the novel begins. All but six of the personnel have died suddenly, due to unknown forces released by an experiment operating within the newly discovered magneto-gravitic or electro-gravitic spectra. The surviving scientists soon learn that they can selectively kill people by releasing the internal pressure of their cell membranes, among other things. Using this discovery, they construct a race-selective weapon that will kill only Asians.