The remarkable story of Sumner Redstone, his family legacy, and the battles for all he controls.

Sumner Murray Redstone, once feared as the “mad genius” of media who would dump his CEOs for mere wobbles in his companies’ stock price, had built one of the world’s greatest media empires through a series of audacious takeovers constructed to ensure that he always maintained control. Today he controls 80% of the voting shares of both Viacom and CBS, meaning that on a whim he could replace the entire boards of two public companies with a combined value of $40 billion. He spent decades performing meticulous estate planning so that his control would extend beyond the grave (which he loved telling reporters he would never lie in), constructing trusts designed to make it impossible for his heirs to sell his companies after he died. “Unless they start doing terribly,” he told the Wall Street Journal in 2012, “which they will not.”

As readers will discover in The King of Content, Redstone’s confidence at the time was not misplaced. His life up to that point had been a story of exceeding expectations, climbing from the son of a linoleum peddler in the Jewish immigrant tenements of Boston’s West End to Harvard Law School, from the president of his father’s regional drive-in movie chain to the owner of Viacom, from a cerebral lawyer who shopped at Filene’s Basement to the owner of a coveted Hollywood studio, and ultimately, after the Viacom-CBS merger, to the controlling shareholder of the largest merged media entity in U.S. history. The credo that he coined and repeated for decades—“content is king”—turned out to be more true in the digital world than he could have ever guessed.

Through exclusive interview and hundreds of pages of legal documents, Keach Hagey reveals the story behind the rise and fall of this remarkable figure, and the details of the family members fighting for control of his vast empire. At the heart of all the dueling lawsuits running through the Redstone family is Sumner Redstone’s tumultuous love life —particularly the fallout from his 2002 divorce from Phyllis, his wife of 52 years. More recently, Redstone’s life has become a tabloid soap opera thanks a lawsuit brought by one of his ex-girlfriends, Manuela Herzer. If the judge finds him incompetent, it will greatly increase the pressure on his trustees to begin the process of placing his controlling stakes in the hands of a seven-person trust who are expected to duke it out over what will become of the companies.

Yet the appetite for Redstone’s assets is not what it would have been just a few years ago. While CBS—bolstered by its sports rights and the programming prowess of its former actor CEO, Les Moonves—has experienced modest declines in the age of cord-cutting, Viacom’s fall has been dizzying. Ratings at its biggest cable networks, which include MTV, Comedy Central, Nickelodeon, BET, and Vstrong, have been falling double-digit percentages for years. A few small cable companies, annoyed at Viacom’s demands for price hikes for their entire package of dozens of channels when ratings were so weak, dropped them altogether last year—a move widely viewed as a canary in the industry coal mine.

There’s a corporate whodunnit here, as well as a series of mysteries that has captivated both the business and tabloid press. The answers lie in family feuds, corporate battles and alliances that go back decades, and will be laid bare in this ambitious book.