Actors often say they strive to show a different side of themselves in their latest films. But actor Gang Dong-won’s performance as Dr. Cheon in “Dr. Cheon and the Lost Talisman,” seems very familiar, as if he intended to act like he has done in the past. His comical swordsmanship and his impactful role as Dr. Cheon is reminiscent of his characters in “Jeon Woo-chi: The Taoist Wizard” (2...