Marguerite Elizabeth Cardwell was 31 when she disappeared from Calgary in early autumn 1973. The last known contact was September 10, when she told a friend she planned to travel, possibly to Edmonton or as far as Vancouver. A few days earlier she had bought a .303 calibre hunting rifle.

Between September 16 and 18 her car was found abandoned on a remote stretch of the Number 1 Highway about 12 miles east of Canmore, in Dead Man’s Flats. Her purse and keys were inside the vehicle. A two-day RCMP search of the surrounding rugged terrain turned up no trace of Marguerite or the rifle.

Initial investigators considered suicide, partly because she had a prior attempt, but a roommate later said a man had been at their suite door the night she disappeared, shouting at her, which raised the possibility of foul play. The investigation has been reopened periodically and her daughter has provided a DNA sample. Does anyone remember Marguerite, her travels in September 1973, or seeing her car along that highway?