Kevin Costner on “Horizon: An American Saga”

Actor-director Kevin Costner won two Academy Awards for “Dances with Wolves,” and now he’s back with another western: “Horizon: An American Saga,” a four-part epic about pioneers settling the West, which Costner himself helped bankroll. He talks with correspondent Tracy Smith about his decades-in-the-planning story (the first two chapters debut in theaters this summer), and about his future on the modern-day western series “Yellowstone.”