Viacom, whose properties also include the CBS and MTV Networks, said Grey, 47, a high-profile Hollywood talent agent and television producer, will start March 1 at Paramount's Los Angeles headquarters.
As chairman and chief executive, Grey will take over the duties of Paramount's former creative head, Sherry Lansing, and of the studio's former head of business, Jonathan Dolgen, who left seven months ago. Lansing is retiring this year. Grey will report to Viacom's co-president and co-chief operating officer, Tom Freston.
Notable deaths of 2014 [PHOTOS]