Two dentists are alarmed by the unsafe and fraudulent practices that they say were standard at a pediatric dental chain that provides services in underserved communities. Fearing that it would lead to overtreatment, overbilling and putting children at risk, they decide to take matters into their own hands.

An office manager at a cancer center blows the whistle on the oncologist running the practice when he discovers the doctor giving chemotherapy to more than 500 patients who do not need it.

James Holzrichter thought he had landed his dream job working at Northrop, one of the top military contractors in the world.

Dr. Michael Jones, a successful cardiologist in Lexington, Ky., noticed a troubling pattern in the patients showing up in his office. They were all from the same part of rural Kentucky, and each of them seemed to have had expensive heart procedures he believed they didn't need.

Los Alamos National Laboratory is the birthplace of the atomic bomb and home to some of the country’s most dangerous secrets. Following a series of embarrassing security lapses and thefts, former police chiefs Glenn Walp and Steve Doran were brought in to review and bolster security at the facility in 2002. But almost immediately, it was clear that things were far worse than they had thought. Host Alex Ferrer examines the whistleblower case against Los Alamos.