More than 42 years after Sheila and Katherine Lyon vanished from Wheaton Plaza, Lloyd Lee Welch was set to go on trial for their murders in remote Bedford, Virginia. Would the Lyon family finally get the answers and justice they've sought for decades?

The 1975 disappearance of two young sisters from a suburban Maryland shopping mall traumatized the nation's capital, upending a family and the community's sense of security. More than 40 years later, the Lyon sisters bodies have never been found, but a man is set to stand trial for their murders.