The Penultimate Truth by Philip K. Dick

In a bleak future a vast population is kept in subterranean “tanks” and fed the lie that an apocalyptic war still rages above, while a privileged surface elite actually lives in comfort and runs a profitable war economy through automated fighting machines. When members of the tank society and a few surface operatives begin to uncover the deception, conspiracies, betrayals and moral ambiguities surface as they struggle to expose the truth and overturn a system built on illusion and control.

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