In 2014, Erika Cheung made a discovery that would ultimately help bring down her employer, Theranos, as well as its founder, Elizabeth Holmes, who claimed to have invented technology that would transform medicine. The decision to become a whistleblower proved a hard lesson in figuring out how to do what's right in the face of both personal and professional obstacles. With candor and humility, Cheung shares her journey of speaking truth to power -- and offers a framework to encourage others to come forward and act in the service of all.