On New Zealand Retro this week we are winding the clock back to 1975. American Lynne Cox became the first woman to swim across Cook Strait in that year. It took her 12-hours, just slightly slower than the Awatere on one propellor. Eighteen-year-old Mona Elizabeth Blades vanished while hitchhiking from Hamilton to Hastings. Her body and belongings have never been found and her case remains one of this country's longest unsolved murders.