For 38 episodes Game of Thrones has consistently managed to incorporate around 5 equally interesting, entertaining and concise different storylines into the hour-long time slot. Before we go any further, yes The Battle of Blackwater only focused on Kings Landing but considering there are triple the characters in Kings Landing than the wall the episode was able to flit between lots of different storylines within Kings Landing rather than having to stretch it out with gratuitous battle scenes. This week's 39th episode 'The Watchers On The Wall' was very different and focused solely on one battle between The Nights Watch and the wildlings and, primarily, Jon Snow. There was just one main storyline with one main focus and this is why single-focus-episodes do not work:
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