The Mist by Stephen King was subsequently included in the Skeleton Crew collection, but has since been published as a stand-alone novella.
The Mist - Stephen King book description:
David Drayton, his son Billy, and their neighbor Brent Norton head to the local grocery store to replenish supplies following a freak storm. Once there, they and other local citizens are trapped by a strange mist that has enveloped the town and in which strange creatures are lurking.
As the mist takes its toll on the nerves of those trapped in the store, a religious zealot, Mrs. Carmody begins to play on their fears to convince them that this is God’s vengeance for their sins and that a sacrifice must be made and two groups—those for and those against—are aligned.
When it is realized that staying in the store may prove fatal, a small group including the Draytons, store employee Ollie Weeks, Amanda Dumfries, Irene Reppler, and Dan Miller attempt to make their escape. They find that what’s “out there” may be worse than what they left behind.
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