Essie Davis
Actress Essie Davis has joined the "Game of Thrones" cast in Season 6. Above, Davis appears at the premiere of "Valley of Love" during the 68th annual Cannes Film Festival in France May 23, 2015. HBO

HBO’s “Game of Thrones” television series has almost caught up to George R.R. Martin’s “A Song of Ice and Fire” book series, but Season 6 still has a couple of storylines to bring from the pages to the screen. The casting of “The Babadook” actress Essie Davis hints at a potential storyline involving Arya Stark (Maisie Williams).

Entertainment Weekly broke the news Saturday that Davis signed on to appear in the sixth season. However, her character left some fans confused -- she was cast as Cersei Lannister, a role that has been played by actress Lena Headey since Season 1. But those worried about Headey being recast shouldn’t worry. Davis’ character is a member of a traveling theater. They’re putting on a play called “The Bloody Hand,” in which Davis’ character plays the queen mother, Cersei Lannister.

This won’t be the first time that “Game of Thrones” has had a play within the show. Viewers will remember that Joffrey Baratheon’s (Jack Gleeson) wedding to Margaery Tyrell (Natalie Dormer) featured dwarfs putting on a play called the “War of the Five Kings.” [Click here to watch the scene.] However, the play in this case may be important to the plot of the show.

According to TV Guide, “The Bloody Hand” is a dramatization of all the events that have happened in Westeros since the beginning of the TV series. The theater troupe brings the play to Braavos, the city where Arya is currently staying.

In “The Winds of Winter” book, a young girl named Mercy is one of the troupe members. She plays a young woman who is raped and murdered by a “demonic dwarf.” Fans can assume that Mercy is playing Sansa Stark (Sophie Turner) and that the “demonic dwarf” is Tyrion Lannister (Peter Dinklage).

Before the play begins, Mercy spots a man from Westeros who she finds to be attractive. She approaches him and takes him back to her room. Before things can get physical, Mercy tells the man he is bleeding. The man is unable to walk, but Mercy does not attempt to get him help. It’s revealed that Mercy is actually Arya, using another face, and the man is Raff the Sweetling. In the books, Raff is one of Ser Gregor Clegane’s (Hafthor Julius Bjornsson) men, responsible for capturing Arya and Gendry (Joe Dempsie). Arya watched him commit numerous horrific crimes while captured, and added him to her kill list.

arya stark
In "The Winds of Winter" book, Arya (Maisie Williams) disguises herself as a young girl named Mercy. HBO

Book readers will recognize the name Raff the Sweetling, but the character was never actually cast in the TV series. However, a similar scene did play out at the end of Season 5. Those who watched the finale will remember that Arya discovered Ser Meryn Trant (Ian Beattie) in Braavos. Although she was supposed to kill a merchant, she decided to get vengeance by killing Ser Meryn at a brothel. Arya was ultimately punished by the Faceless Men for taking a life from the Many-Faced God. Her punishment was losing her sight.

Could Ser Meryn’s death be HBO’s version of Raff the Sweetling’s death from the books? Or will Arya be taking more lives when Season 6 of “Game of Thrones” returns? Although it’s unclear how her loss of vision will play out on the show, photographs taken on the set make it appear as if Arya will share scenes with Davis’ Cersei Lannister character.

“Game of Thrones” Season 6 premieres on HBO in 2016. How do you think “The Bloody Hand” play will tie to the plot? Tweet your thoughts to @AmandaTVScoop.