Game of Thrones continues to thread seminal events in season one to tragic conclusions in season six. Episode five, The Door, answers two of the show's greatest mysteries. The White Walkers creators are revealed, as well as the tragic destiny of Hodor (Kristian Nairn); the benevolent, simpleton giant who has carried and protected Bran Stark (Isaac Hempstead Wright). This conclusion was a whopper. The sanctity of The Three-Eyed Raven (Max von Sydow) is shattered as The Night King finally makes his move.

"The Door" begins with Littlefinger (Aiden Gillen) arranging a secret meeting with Sansa (Sophie Turner) in Moles Town. He is surprised that she has brought Brienne (Gwendoline Christie) as security. Sansa bitterly rebukes Littlefinger for delivering her into Ramsey Bolton's (Iwan Rheon) sadistic clutches. She no longer trusts him. Sansa recounts the horrifying abuse. Female characters are brutalized without recourse or discussion. This was a much needed moment in Game of Thrones. Littlefinger is dispatched spitefully, but not before telling Sansa that her granduncle, Brynden Tully aka The Blackfish, is alive and gathering forces.

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Arya (Maisie Williams) continues to take a beating during her training in Braavos. Jaqen H'ghar (Tom Wlaschiha) believes her noble birth holds her back. Arya swears her loyalty to the Many-Faced God. She is no one. Jaqen decides to give her one last test to prove herself. She must poison an actress, Lady Stork (Essie Davis). Arya sees her play, a humorous and macabre retelling of her father's beheading. She investigates Lady Stork, seeing no crime worthy of her death. Arya asks Jaqen why this woman should die. He reminds her that the good die just as easily as the wicked.

In the far north, Bran and The Three-Eyed Raven are in a trance. Bran learns a shocking truth. He sees The Children of the Forest create The Night King. They are responsible for The White Walker threat. The undead soldiers were their defense against man's encroachment.

Meanwhile in the Iron Islands, a Kingsmoot is taking place. Yara Greyjoy (Gemma Whelan) stakes her claim to be the first queen of the Iron Borne. Theon (Alfie Allen) gives up his right as the male heir, then publicly lauds his sister. Their campaign is stopped in its tracks by Euron Greyjoy (Pilou Asbæk). He admits to killing his brother Balon, the only regret is not doing it sooner. Euron makes his pitch to rule. He claims that he will wed Daenerys Targaryen (Emilia Clarke). Then take her dragons and his army of ships to conquer Kings Landing. Euron wins the crown. But while he is baptized by near drowning, Yara and Theon escape with the best ships in the fleet.

Daenerys has a heartfelt reunion with Ser Jorah (Iain Glen) and Daario (Michael Huisman). Ser Jorah admits his unrequited love and obedience to her. He then shows Daenerys his affliction with The Stone Man disease. She weeps for the man who has been her stalwart protector. She orders to him to find a cure, and then promptly return to her. She will need him at her side when she rules from the Iron Throne. Daenerys gathers the Dothraki and embarks for Mereen. Ser Jorah watches them leave, then rides away.

At council in Mereen, Tyrion's (Peter Dinklage) bargain with The Masters has seemingly quieted the Harpy insurrection. He knows the peace is fragile, that they need a respected ally to reinforce Daenerys' rule. He summons Kinvara (Ania Bukstein), another Red Priestess of the God of Light. Her religious hold over the people makes her an invaluable ally. Varys (Conleth Hill) is not impressed. He was witness to Melisandre's (Carice van Houten) powers and failed support of Stannis Baratheon. Kinvara eerily invokes the night of Varys' castration. He is stunned by her knowledge of this event. Kinvara lends her support to their cause, but Tyrion is wary.

While everyone is asleep in the cave, Bran foolishly enters a trance without the Raven's guidance. He is outside surrounded by White Walkers. He walks through them and comes face to face with The Night King, who grabs him by the arm. Bran awakens with the King's mark on his hand. The Three-Eyed Raven tells him that they have been discovered. That Bran must leave the cave.

At Castle Black, Sansa sits with Jon Snow (Kit Harington), Ser Davos (Liam Cunningham), and Brienne. They don't have enough men to retake Winterfell. Sansa tells them of the Blackfish and his army. She lies to Jon and doesn't reveal Littlefinger as the source. This move by Sansa shows that even though she refuted Littlefinger, his machinations are still in play. The group gathers to leave Castle Black to recruit Brynden Tully. Sansa has knit a dress with the Stark's wolf insignia emblazoned across the chest. She has also branded Jon Snow's clothing with the mark of the wolf.

The White Walkers have arrived at the cave. Meera (Ellie Kendrick) races to wake up Bran. He is in a time trance with the Raven, observing his father at Winterfell as a boy. The Children of the Forest fight the Walkers to the death. They are overcome and the cave is breached. Meera tries to awaken Bran, screaming that they need him to control Hodor. In the trance, The Three-Eyed Raven tells Bran to heed her words, and that the time has come for him to take his place. Bran asks if he is ready, the Raven replies no.

Hodor, now under Bran's control, grabs him and runs away with Meera. Bran's direwolf is killed as they escape. The Night King enters the cave and runs his frozen sword through The Three-Eyed Raven. Meera takes Bran and pulls him out of the cave. She screams for Hodor to "hold the door". Still in the trance, Bran looks towards Wylis, Hodor as a boy. Meera's words echo into his head. Willis has a seizure and falls down, continuously repeating "hold the door"; until it blurs into "hodor". Bran now understands that he was responsible. As Meera drags Bran off into the snow, Hodor holds the door against the White Walkers, as they slowly rip him to shreds.

Last week Osha and now poor, brave, wonderful Hodor dies a horrible death. Or at least we think he does. The Door cuts to black as Hodor, dutifully holding the door to enable Bran and Meera's escape, is savagely cut down. The revelation that Bran, through the time trance, caused Hodor's mental affliction is just extraordinary. The White Walkers attacking the cave is the most significant event of the episode, but Hodor's fate is damned heartbreaking. The good certainly don't survive in Game of Thrones. Jaqen H'ghar's lesson to Arya is spot on. HBO truly outdoes themselves once again.