We Journey No More by Sahara Foley

A desert wasteland.
Mutant lifeforms.
Humans on the verge of extinction.

Teenagers Don and Janet run off to California to start a new life together. Along the way, they find themselves in a dangerous land. Did they inadvertently time travel to a future Earth? Or, a parallel universe?

The young couple is rescued by one of the nomadic tribes who survived a global nuclear war. These small groups journey endlessly, searching for food and water. Whatever they discover is taken by the brutal leaders of the Ganu Camp. Yearning to break free from enslavement, they hail Don as their prophesied savior. Now, faced with a lost-cause battle, the teenagers must defend their new friends with the only weapons available to them. How will they defeat a powerful enemy with only skyrockets, firecrackers, and a dog whistle?

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Even though the main characters are teenagers, this is NOT a YA or children book. There are violence and sexual content.