1. The Red Wedding
The event that changes the direction of the entire series, and will shock television viewers as much as it did book readers. The Red Wedding sees The King In The North, Robb Stark, attend a wedding between his uncle Edmure and a daughter of Lord Walder Frey, intended to repair the bad blood between Robb and Walder caused by Robb's decision to marry Talisa Maegyr rather than one of his daughters, as was promised to Walder in Season 1. The damage seems to have be repaired, until unexpectedly, Robb, his mother Catelyn and several of their bannermen all find themselves mercilessly slaughtered at the hands of men loyal to Lord Walder and Roose Bolton, an ally of Robb's who has become disillusioned with his leadership. The action all but ends the Stark's rebellion against the Lannisters, already damaged by the actions of Theon Greyjoy and the Ironborn in Season 2, bringing one of the main stories of the show to a close in a fashion that is guaranteed to leave viewers as astounded as they were upon witnessing the death of Eddard Stark in Season 1, proving once again that in this series, nobody is safe.