When the blood-testing company Theranos opened to the public in 2013, founder Elizabeth Holmes made bold claims of having revolutionized the diagnostic-lab business. With just a few drops of blood pricked from a finger (as opposed to several vials drawn from a syringe in the arm), the company said it could not only run the full range of laboratory tests, but also turn around results within hours, all at a low cost.

Theranos received fawning early media coverage, but last October Wall Street Journal reporter John Carreyrou took a more critical look. With descriptions of unreliable equipment, skeptical employees and deficient practices, he reported that the company’s PR blitz outpaced its actual medical technology. On this week’s podcast, Carreyrou talks with ProPublica senior reporter Charles Ornstein about why he decided to look into Theranos in the first place, the problems with the company’s claims, and the recent actions from federal inspectors and Walgreens that lend credence to his investigation.

[NOTE: After the recording of this podcast, the Wall Street Journal reported that Walgreens threatened to terminate its retail partnership with Theranos unless it addresses mounting problems.]

Elizabeth Holmes, founder and CEO of Theranos, speaks at the Fortune Global Forum in San Francisco, Monday, Nov. 2, 2015. (AP Photo/Jeff Chiu)

Highlights from their conversation: