When the cast of the film “The Hobbit” was first announced, Marlon James was dismayed—though hardly surprised—by how white it was. A long-standing complaint of black fans of fantasy is that authors can imagine dwarves and elves and orcs, but not black characters. “I got so tired of this whole question of inclusion, and the backlash against asking to be included,” James tells the staff writer Jia Tolentino, “that I said, ‘I’m going to make my own damn universe.’ ” That was one origin point of James’s “Dark Star” trilogy, which he describes as “an African ‘Game of Thrones.’ ” The first book, which is about to be published, is called “Black Leopard, Red Wolf,” and it centers on the search for a missing boy by a disparate cast of characters. Another origin point for him was the TV show “The Affair”; James borrowed the structural device of a story related by multiple characters whose perspectives don’t quite add up. James talks about writing fantasy from a Caribbean perspective, where “magical realism” may not seem so magical. Plus, a successful C.E.O. says that activist investors’ quest for one quick stock bump after another is wrecking companies and eroding American competitiveness.