The House of Black and White

"The House of Black and White" is the second episode of the fifth season of HBO's fantasy television series "Game of Thrones", and the 42nd overall. The episode was written by series co-creators David Benioff and D. B. Weiss, and directed by Michael Slovis. It aired on April 19, 2015. Prior to airing, this episode along with the other first four episodes of the season were leaked online. The title refers to colour of the door of the faceless man in which Arya enters. 
Plot.
King's Landing.
In King's Landing, Cersei and Jaime receive a message from Dorne: Myrcella's necklace in the jaws of a viper. Recognizing the threat, Jaime tells Cersei that he will infiltrate Dorne and retrieve Myrcella. He meets Bronn with his betrothed Lollys Stokeworth at Castle Stokeworth and tells him that if he helps him rescue Myrcella, he will be wed to a woman with a larger castle.
At a Small Council meeting, Cersei announces that she will sit in until Tommen chooses a new Hand. She makes Mace Tyrell Master of Coin and Qyburn Master of Whisperers, but her Uncle Kevan declines the office of Master of War and states that he will return to Casterly Rock until he hears directly from Tommen.
At the Wall.
Stannis, unable to win House Stark's former allies to his cause, offers to legitimize Jon as a Stark and give him Winterfell if Jon pledges his service to him. Jon plans to decline, but before he can tell Stannis, he is nominated by Sam to be the new Lord Commander. Jon defeats Ser Alliser after Maester Aemon casts the winning vote.
In the Vale.
Brienne and Podrick stop at an inn, where they encounter Petyr and Sansa. Brienne asks Sansa to exit with her, but Sansa refuses. Petyr tries to capture Brienne, but she escapes with Podrick. Podrick suggests that since both Stark girls have refused her protection, Brienne is released from her vow to Catelyn Stark, but Brienne distrusts Petyr and follows them.
In Braavos.
Terys takes Arya to the House of Black and White, the headquarters of the Faceless Men, but the doorkeeper denies her entry. After wandering the streets of Braavos, Arya encounters the doorkeeper again, who brings her back to the temple and changes his face to that of Jaqen H'ghar's. He grants Arya entry, but tells her that she must become "no one".
In Dorne.
Ellaria Sand hatefully watches Myrcella with Trystane Martell and asks Doran to take action for the murder of Oberyn, but he refuses.
In the Flatlands.
As Tyrion and Varys travel through the Flatlands on their way to Volantis, Varys attempts to motivate Tyrion by reminding him of his skill in ruling.
In Meereen.
Daario and Grey Worm capture a member of the Sons of the Harpy. Mossador, a freedman sitting on Daenerys' council, kills the captive before the trial. Daenerys executes Mossador publicly, inciting a riot between freedmen and masters. At night, Drogon visits Daenerys at the Great Pyramid but flies away.
Production.
Writing.
This episode was written by executive producers David Benioff and D. B. Weiss and contains content from three of George R. R. Martin's novels, "A Storm of Swords" Jon XI and Jon XII, "A Feast for Crows", Arya I, the Captain of the Guards, Cersei IV and partial Cersei II and "A Dance with Dragons", chapter Tyrion II and partial Jon I.
As in the previous episode, several scenes were written specifically for "The House of Black and White" and do not appear in the books. For example, Myles McNutt of "The A.V. Club" commented on the scene in which Brienne meets Sansa, who rejects her offer of help and protection, saying that it creates crisis regarding the character's purpose.
Casting.
With this episode, Tom Wlaschiha (Jaqen H'ghar) and Indira Varma (Ellaria Sand) are promoted to series regulars. Wlaschiha returns after last appearing in the second season. The episode has the introduction of new recurring cast members Alexander Siddig, who plays the Prince of Dorne: Doran Martell, DeObia Oparei, who plays his bodyguard Areo Hotah, and Toby Sebastian, who plays Doran's son Trystane Martell, while Nell Tiger Free replaces Aimee Richardson as the recurring character Myrcella Baratheon.
Reception.
Ratings.
"The House of Black and White" was watched by an estimated 6.81 million American viewers during its first airing, and received a 3.6 rating among adults 18-49. In the United Kingdom, the episode was viewed by 2.164 million viewers, making it the highest-rated broadcast that week. It also received 0.145 million timeshift viewers.
Critical reception.
Reception to the episode was generally positive. Matt Fowler from IGN gave the episode a rating of 8.8/10 stating "The House of Black and White" was a notably bigger, better episode than the Season 5 premiere. It not only brought Arya and Bronn back into the mix and introduced Dorne... it contained huge moments for Brienne, Dany, and Jon." The episode received a 96% score on Rotten Tomatoes from 51 reviews with an average rating of 8.29 out of 10 and the consensus reading: "Building upon the season opener, 'The House of Black and White' increases the intensity by calling upon some major characters to make some tough decisions."