Michael Lynton’s “Black Swan” materialized late last year, when someone—the U.S. government says it was North Korea—pulled off the most devastating hack in corporate history. Lynton, the CEO of Sony Pictures Entertainment, had to look on as highly confidential company information—salary details, private e-mails (some of them harshly critical of top Hollywood talent), unreleased movies—was leaked for all the world to see. For good measure, the hackers wiped out huge amounts of data on the company’s servers.

A version of this article appeared in the July–August 2015 issue (pp.106–113) of Harvard Business Review.