'Game of Thrones' unveils final 'oh s---' moment George R.R. Martin told writers

Warning: Spoilers ahead for HBO's “Game of Thrones” season eight finale.HBO's showrunners David Benioff and D.B. Weiss once said they were told three shocking moments George R.R. Martin that haven't happened in the books yet.The first two were the burning of Shireen Baratheon and the revelation of how Hodor got his name.The third and final shocking moment likely just unfolded on the series finale.Visit INSIDER's homepage for more stories.HBO's “Game of Thrones” came to an end on Sunday night, and with it one of the show's most devastating deaths in the eight-season run. We believe this particular death is the last major twist author George R.R. Martin revealed to the showrunners. Back in 2013, “Game of Thrones” showrunners David Benioff and D.B. Weiss realized their TV adaptation of Martin's “A Song of Ice and Fire” books might soon outpace the source material. So they sat down for a meeting with Martin, in which he told them the “broad strokes” for his planned ending.This is your last warning before we dive into major spoilers for the series finale of “Game of Thrones.”We believe the death of Daenerys Targaryen at the hands of Jon Snow was one of the most surprising things Martin told Benioff and Weiss would eventually happen in his books.In the final episode of the series, Jon Snow killed his queen by stabbing Daenerys in her heart right in front of the Iron Throne. Daenerys dies, shocked by Jon's betrayal, and her body is subsequently carried off by her last living dragon, Drogon.In 2016, the Benioff and Weiss spoke with Entertainment Weekly about how Martin had told them three planned moments for the book series which made them think, “Holy s---.”The first two of these “holy s---” twist was the burning of Shireen Baratheon (which they brought to life on the fifth season of the show) and the revelation of how Hodor got his name (which happened on the sixth season).The third, Benioff said, was from “the very end” of the story. We're taking this to mean it was something from the finale episode of “Game of Thrones,” and therefore Daenerys Targaryen's death is the most likely candidate. While the show has been slowly foreshadowing a tragic turn for the Mother of Dragons, hearing her fate back when only three seasons of the show had been written would have been shocking indeed. At the time Martin had that meeting with Benioff and Weiss, the third season of “Game of Thrones” had aired, showing Daenerys conquering Astapor and Yunkai and on her way to becoming a liberating hero. It would have been hard to believe back then that her quest for the Iron Throne would end with as much destruction and tragedy as we just watched play out on the series finale. For more on Daenerys Targaryen's death and how it played into a major prophecy from Martin's book series, read our full explainer here.For more “Game of Thrones” insights and analysis of all the best moments in the series, preorder the “The Unofficial Guide to 'Game of Thrones'” now.Read more:Every detail you might have missed so far on 'Game of Thrones' season 8THEN AND NOW: How the 'Game of Thrones' characters have changed since the first seasonAll the new changes in the 'Game of Thrones' opening credits you might have missedBEFORE AND AFTER: 9 'Game of Thrones' characters that were recast