Kaliyua, or Kaliyuga, "age of (the male demon) Kali", or "age of vice" is the last of the four stages that the world goes through as part of the cycle of yugas described in the Indian scriptures. Hindus believe that human civilization degenerates spiritually during the Kali Yuga, which is referred to as the Dark Age because in it people are as far removed as possible from God. The Dark Age, is replaced by the shadow of Conrad's novella Heart of Darkness, which in turn inspired Francis Ford Coppola's film Apocalypse Now, which gives the twist to the title. Here the spiritual energy which courses through the spine is replaced by the image of Nuclear explosions.