The Spencer family is part of a wagon train passing through Chugwater, Wyoming, bound for the valley of Longshot Basin. Unfortunately, the trail that leads there has been buried under an avalanche. The only route the homesteaders can take is the infamous Nightmare Trail—a  treacherous, terrifyingly steep and narrow mountainside path that has claimed many lives.
 
If that wasn’t dangerous enough, the trail is also a killing ground for the outlaw Hardcastle gang. The disreputable Arkansas Ozark clan don’t take kindly to anyone trespassing on their road without paying—in blood.