In a small Tennessee town, teacher Alex Campbell turns his sociology class into an unlikely force for truth. What begins as a 40-year-old cold case study becomes a legacy project, as each year's students uncover evidence suggesting these weren't isolated murders-but pieces of a larger pattern along America's highways.

Evidence begins to suggest their lead suspect wasn't a one-off killer but tied to at least six victims. Focusing on the strongest cases, they gather evidence that could force authorities to brand him a serial killer, edging closer to a federal investigation that may rewrite history. The breakthrough brings more questions than answers. Are they uncovering the truth or blinded by confirmation bias?

For the first time, the class partners with investigators-visiting crime scenes, engaging locals, and launching a headline-making campaign. But unlike TV true crime, they learn real change is slow and incomplete. As the school year ends, roadblocks and unanswered questions force them to ask: can justice exist without closure?