"Game of Thrones" Season 4, Episode 7, titled "Mockingbird," airs May 18 on HBO. Arya Stark, Tyrion Lannister, Daario Naharis, Sansa Stark and Petyr Baelish are all in this week's new episode. Their stories move forward as the third GOT season draws to a close. Watch the promo video for spoilers and teasers.

Spoiler alert: This feature contains spoilers on Game of Thrones Season 4. Some details from George R.R. Martin's book series are also mentioned. Read at your own risk.

Tyrion Lannister (Peter Dinklage) wants a trial by combat. Readers of George R.R. Martin's "A Song of Ice and Fire" book series know that this combat is linked to Prince Oberyn Martell (Pedro Pascal) and Gregor Clegane/The Mountain (Hafþór Júlíus Björnsson). Game of Thrones Season 4, Episode 8 is titled "The Mountain and The Viper" in reference to these two.

Tywin Lannister (Charles Dance) dies in Game of Thrones Season 4, assuming HBO showrunners D.B. Weiss and David Benioff are sticking to GRMM's books with regards to the death of the Lannister patriarch. For now, Tyrion's hate for his father is building up. The climax of their confrontation is expected to be seen in next week's new episode, after the aforementioned combat.

Arya Stark (Maisie Williams) and The Hound/Sandor Clegane (Rory McCann) are also featured in the Game of Thrones Season 4, Episode 7 promo video. Arya is Braavos-bound toward the end of "A Storm of Swords," the third book in GRMM's ASOIAF. The Hound dies before Arya sails off, and this could be where the HBO adaptation is going, too.

Daenerys Targaryen (Emilia Clarke) considers giving Daario Naharis (Michiel Huisman) a longer leash, says the GOT 04x07 episode synopsis on TV.com. In the promo video, he seems to be convincing Daeny to give him a chance to prove his loyalty.

Sansa Stark (Sophie Turner) and Baelish/Littlefinger (Aidan Gillen) may have a bigger story in this Mockingbird-titled episode. (Littlefinger wears a mockingbird as his personal crest.)

In the Game of Thrones 04x07 promo video, Sansa's aunt, Lysa Tully (Kate Dickie), appears to have gone mad(der), and jealousy may be the reason. In 'Storm,' Littlefinger pushes Lysa into the Moon Door. His "partner in crime" hopes for Sansa may be coming true.

Jon Snow (Kit Harington) has a big story in the 'Storm' book. His "warnings about the Wall's weaknesses are ignored," in GOT 04x07, reports TV.com. Stannis Baratheon (Stephen Dillane) and the Red Priestess Melisandre (Carice van Houten) will try to get Jon Snow on their side, and it could happen soon on HBO.

WATCH: 'Game of Thrones' Season 4, Episode 7 ('Mockingbird') | HBO on YouTube

Also present in Game of Thrones Season 4, Episode 7 are Brienne of Tarth (Gwendoline Christie) and Podrick Payne (Daniel Portman). The next new episode airs May 25 on HBO.

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