Beyond the Valley of Mist

A tribe of stone aged people lived in a village of caves carved into a sandstone cliff by a stream that flowed into a valley shrouded by a perpetual mist. The village was called Lalock, and the Lalocks called the Valley of Mist the valley of death, because a few people entered the mist but none returned. The Lalocks worshiped fire, but they were unhappy because the wicked High Priest ruled with an iron hand and sacrificed anyone who defied him to the fire.
Before girls could marry, they were required by religious law to submit to the priests until they become pregnant. If they refused, or if they failed to get pregnant, they were sacrificed to the Fire God. Two young stone age couples want to marry, but the priests will not permit it until they have impregnated the girls. The two young men refuse to share their loved ones with the priests, so the four attempt to escape into the Valley of Mist by floating down the river on a log raft.
They face uncertainty and death in search of a better life. Does the valley have another side? And what horror must they endure to reach it, and if they find the other side, what will they have to do to survive?