Holmes’s idea of inventing a cheap, small, fast, reliable blood-testing system to creatively destroy most of the world’s existing infrastructure for blood tests ran into big problems early on. But with her chutzpah, persuasiveness, and eventually with the help of outright obfuscations and lies, Holmes kept Theranos going until a Wall Street Journal investigative reporter named John Carreyrou responded to a lead by a health-care blogger that something fishy was going on.