On a warm Sunday morning in rural Ballarat, a mum of three laced up her running shoes, and stepped outside for what should have been a normal run. And then vanished without a trace. 

She knew the bushland like the back of her hand. So how the hell did she fall off the face of the earth? 

The trail abruptly ended, and the mystery gripped Australia. This is the chilling case of Samantha Murphy.