Mary Ann Plett was a 29-year-old married mother of two and a real-estate agent with Graham Realty Ltd. On September 15, 1971, she left Edmonton to meet a prospective buyer who called himself James Cooper and wanted to view an acreage in the Looma area about 30 kilometres southeast of the city. She never returned from that appointment.

Two days later her locked car was found abandoned at a south Edmonton used-car lot with two small human bloodstains inside and a crumpled wig similar to one she owned; other accounts reported blood in the trunk and signs the vehicle had been driven off paved roads. Weeks later her briefcase and real-estate papers were found near Fort Assiniboine, roughly 160 kilometres northwest of Edmonton, and in April 1972 searchers found clothing, a skull, and skeletal remains. The remains were too decomposed to establish cause of death.

Investigators never identified the man calling himself James Cooper, who had been the last known person with Plett; police followed multiple leads over the years but no one was charged. The case remains unsolved. Does anyone have information about the man who arranged that appointment or about Plett’s movements on September 15, 1971?