Heaven Sent is a deeply unnerving story that begins with a mystery and devolves into psychological horror. The best episodes of Series Nine have dealt with current issues and Heaven Sent is no exception. Torture is something that many so-called civilized countries still practice even when its been shown that it is not an effective interrogation tool. In the effort to circumvent terrorism we allow ourselves to become the monster we seek to avoid. At the end of each cycle the Doctor is left desperate, broken and dying on the floor. We are shown trails of blood and burnt skin as he crawls his way back to the tower. Doctor Who is seldom so graphic but does not hesitate to show the depth of this mans suffering. Writer Steven Moffat and the production team take care to inform us that the Doctors actions have real consequences. Nothing is sugar-coated.