Two stars (out of four) Rated R, 169 minutes As acclaimed as the first half of Stephen King’s “It” adaptation was in 2017 — it quickly became the highest-grossing horror film in U.S. history — there was never any guarantee that “Chapter Two” would live up to it. Optimism, maybe, but no guarantees. Director Andy Muschetti and his screenwriters decided to split King’s New York Times best-selling, 1986 horror novel into two parts that would be released two years apart.