Joanne Gladys Thornton, also known by her married name Joanne Garr and the nickname Joan, disappeared from the Detroit area in late 1971. Her final confirmed contact was on November 24, 1971, in Dearborn Heights, when she arranged Thanksgiving plans with her first husband so their two young daughters could attend a downtown parade; she never showed up for those plans nor for a planned dinner and stopped reporting for work. Records also list December 29 and Detroit as possible last-known details, but the stronger account places her last confirmed contact the day before Thanksgiving.

Less than a year earlier she had married Philip Garr; family members say the marriage had been strained. Philip gave inconsistent accounts of Joanne’s whereabouts, at different times saying she had gone to Ohio, Illinois, or left with an unknown man in a car with Ohio plates. Joanne had been seen with bruises and black eyes that she called the result of a fall. Her car was later found abandoned. A delay in reporting her missing and the return and discarding of mailed personal items removed potential evidence. A DNA sample from one daughter was later collected to compare with unidentified remains. No resolution has been reported.

Did anyone in the Detroit, Dearborn Heights, Ohio or Illinois areas remember seeing Joanne, her car, or the vehicle with Ohio plates in late November or December 1971?