1. The Red Wedding
Season 3, Episode 9: "The Rains of Castamere"
It began with a music cue, the most ominous opening notes this side of John Williams' Jaws theme. The moment that the wedding band began playing the Lannister anthem "The Rains of Castamere," both Lady Catelyn Stark and we at home knew something was wrong. We just had no idea how wrong it could get.
What followed instantly entered the pop-cultural pantheon of shocking TV, placing the phrase "the Red Wedding" right up there with "Who shot J.R.?" Betrayed by Walder Frey and his partner in crime Roose Bolton, the Starks were ruthlessly slaughtered: King Robb shot multiple times and stabbed in the heart; his pregnant Queen Talisa and their unborn child knifed to death; and his mother Catelyn done in by a slit throat, collapsing to the floor to end both the episode and all hope of Stark victory. Whether you first attended the bloody nuptials while reading the third book in Martin's series, A Storm of Swords, or caught it on HBO in the penultimate episode of the show's third season, chances are good some part of you feels like you never made it out.