Sharlto Copley is on screen for nearly the entirety of “Ted K,” which follows the Unabomber, Ted Kaczynski, in the years leading up to his arrest. But the man himself remains inherently unknowable—fearsome and fascinating but just out of reach. And that’s probably by design in the impressionistic and hypnotic drama from director Tony Stone. My review, at RogerEbert.com.