At the core of this episode is a set of double-crosses, executed so carefully that every revelation uncovers another layer of complexity. All signs point toward Anton Karidian as mass murderer, but the certainty that builds around this conclusion is accompanied by doubt as to what consequences that should bring him, when it is learned that not a remorseless Anton, but his daughter, Lenore, has been covertly eliminating the potential whistle-blowers. So, Kirk has used Lenore even as Lenore was using Kirk, neither one initially aware of the other's intentions, and somehow, it is a mass murderer that is made the innocent victim of this crossfire. That is some stellar writing.