Elizabeth Holmes promised the world a healthcare revolution and made a fortune along the way.
Her start-up company, Theranos, became the darling of Silicon Valley thanks to a miniaturised machine she claimed could diagnose up to 200 diseases from a single finger prick of blood.
Alongside her business partner and then-secret lover, Ramesh "Sunny" Balwani, Holmes turned the business into a $9 billion juggernaut.
But it was all built on a lie.
Her supposed medical miracle didn't work, and even worse, it was potentially putting lives at risk as a result.
'Day one working with it, it was obvious that it didn't work'
But the world may never have known her outrageously dangerous lie if it wasn't for two of Holmes' own scientists, who risked everything to expose the truth.
"It's a bit of a heart-breaking tale, because there was so much potential," Erika Cheung told 60 Minutes reporter Tara Brown.
When they first joined Theranos, Cheung and Tyler Shultz were both fans of Elizabeth Holmes and believed they could help her change the world.
But the young pair's optimism quickly evaporated when they were given access to her fabled blood testing machine.
"Day one working with it, it was obvious that it didn't work," Schultz told 60 Minutes.
No matter how many tests they ran, the device failed to deliver reliable results, but that didn't stop Holmes and Balwani from spruiking it to the world.
Their cavalier, non-stop promotion of the machine was alarming.
"All of a sudden it's just like...
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