On February 24, 1978, five friends from Northern California drove to Chico to watch a college basketball game. They were expected home that night because they had an important basketball tournament of their own the following day. Instead, all five disappeared.

Days later, their car was discovered abandoned high in the mountains, far from their expected route home. Months afterward, four of the men were found dead in the surrounding wilderness. Evidence suggested that one had survived for weeks inside a Forest Service trailer. The fifth man, Gary Mathias, was never found.

Why did five men who expected to be home that night drive into the mountains, abandon a functioning car, and walk into freezing wilderness?