It's amazing how some of the best TV I've ever seen has been just two people in one room talking. The best episode of Masters of Sex was "Fight" with Sheen and Caplan, in a hotel room, supposedly talking about boxing. The best episode of Homicide was "Mercy" with Braugher and Woodard in the 'box' talking about euthanasia. This episode was a twofer, with two alternate universes, one beautiful and full of grace, one ugly and full of fear, each rendered completely and believably from the same two people inhabiting each. I found it utterly breathtaking, a testament to the prodigious talent that has graced this series.