Theranos Whistle-Blower Tells of Being ‘Star-Struck’ by Holmes

Erika Cheung told jurors she was “star-struck” when Elizabeth Holmes interviewed her for a job at Theranos Inc. but eventually quit the blood-testing startup because she was “uncomfortable” with how patient samples were processed.

Cheung’s potential to deliver devastating testimony at Holmes’s fraud trial was clear before she took the stand Tuesday. She knows from the inside the deepest secrets at the company Holmes founded, and her decision to speak up about the wrongdoing she claims to have detected at the company is a central reason Holmes faces as long as 20 years in prison if she’s convicted.

She testified ...