On a summer day in June 1978 the Lorenz family stopped on Interstate 35 near Purcell, Oklahoma to help a woman who appeared stranded. Melvin George Lorenz, 38, was driving with his wife Linda, 31, and their 12-year-old son Richard. The woman, Verna Stafford, was acting as a decoy while her husband Roger Dale Stafford and his brother Harold waited nearby. When Melvin approached, the two men emerged; the family was robbed and then shot and killed. Their bodies were later found in a field.

Investigators linked the Lorenz murders to a mass murder at a Sirloin Stockade in Oklahoma City a few weeks later and identified Roger, Verna and Harold Stafford as suspects. Harold Stafford died in a motorcycle accident before he could be prosecuted. Verna Stafford agreed to a plea deal and testified that Roger was the triggerman; her testimony helped secure his conviction. Roger Dale Stafford was later executed and Verna received two life sentences.

Did anyone who knew the Lorenz family or was traveling I-35 in June 1978 notice anything that day?