The killer of Lara Grandfelt's twin sister Doris was never found. Twenty years later she's determined to find Doris's killer once and for all. She offers a $5 million reward for information leading to the killer's arrest. Dozens of true-crime bloggers show up looking for both new evidence and "clicks," and Lucas Davenport and Virgil Flowers are called in to review anything that might be a new lead.