Martha's twin brother, Lawson Green, picked Martha up from her hostess job at the Holiday Inn on April 15, 1987. They were driving back to their family's residence in White Bluff, Tennessee in a Monte Carlo with tinted windows that Lawson had borrowed, when the vehicle ran out of gas on Highway 46 near Fabric Road in Dickson County, Tennessee at approximately 9:00 p.m. A family pulled in behind them and offered to help. Martha said she was scared and Lawson said she should come with him and the family so they could get gas, but she said she'd stay behind. Lawson left with the family to purchase fuel. Martha was left alone in the car. He discovered she had vanished upon his return. Martha's handbag was still inside the vehicle, as were the keys. Authorities had a suspect in Martha's disappearance, Robert McKinley Richards. He took investigators to several places where he claimed he had buried Martha's body, but searches of those locations turned up no evidence. Richards was subsequently murdered in prison, but he is still considered the primary suspect in her disappearance.