'House Of The Dragon': The Solution To Rhaenyra's Rat Problem Has A Surprisingly Big Impact In 'Game Of Thrones'

WARNING! SPOILERS for House of The Dragon 3x04, 'Tumbleton'.

Ever since taking back her rightful place on the Iron Throne in the second episode of House of the Dragon's third season, Queen Rhaenyra Targaryen has been dealing with a persistent rat problem in the Red Keep. Alyn of Hull, the illegitimate son of Lord Corlys Velaryon, offers a surprisingly simple solution that, unbeknownst to either Alyn or Rhaenyra, ultimately has a big impact on the future of Westeros.

Let's look at where the rat problem started, and how Alyn's plan to fix it may have indirectly saved the realm hundreds of years in the future.

Aegon's Revenge

The seeds of the rat problem were sewn in the first episode of House of The Dragon's second season. A pair of assassins, Blood and Cheese, are hired by Daemon Targaryen to bring him the head of Aemond Targaryen in retaliation for the death of Prince Lucerys Velaryon, but instead murder Prince Jaehaerys Targaryen, the young son and heir of King Aegon II. Cheese, a rat-catcher, used his knowledge of the castle tunnels to sneak himself and Blood into the castle.

Blood is intercepted before leaving the city. He reveals a rat-catcher was his accomplice in Jaehaerys's murder, but the investigation fails to reveal exactly which rat-catcher was responsible.

Aegon, mad with grief over his son's death, orders every rat-catcher in the city hanged. Unfortunately, this results in a rodent population boom.

Rhaenyra, the Rats, and the Cats

By the time Rhaenyra takes the throne in season three, the rat problem is growing to near plague levels. She gets rid of some by feeding them to the food-hoarding nobles to make a point, but this unfortunately does not entirely solve the problem.

In 3x04, a rather frustrated Rhaenyra finds that rats have invaded the remains of her late father King Viserys's model of old Valyria. It is at this point that Alyn mentions keeping cats on his ships as pest control.

If the books are believed, cats do end up being a part of the future King's Landing pest control regime. Fire & Blood credits Otto Hightower with the idea to release cats in the Red Keep, but as it has been established that most of the testimonies in that book are biased in favour of the Greens, this matter is open for debate.

Whoever's idea it was, the cats become a fixture of the Red Keep, breeding and thriving over the years. In the A Song of Ice and Fire novel series, Varys recalls that Princess Rhaenys (No, not that one.. Damn Targaryren names), the eldest child of Prince Rhaegar Targaryen, had adopted a black kitten from among the Keep Cats, naming it Balerion after Aegon the Conqueror's famous dragon. A particularly mean and haggard cat slinking through the castle tunnels during the first book, A Game of Thrones, is hinted to be the adult Balerion, gone feral after little Rhaenys's death.

King Tommen's pet cat, Ser Pounce, is also most likely a descendant of the cats released in the Red Keep during the Dance of Dragons.

How the Cats of the Red Keep indirectly save Westeros from the Long Night

The cats in the Red Keep are not just a throwback to House of The Dragon's rat problem. In fact, they actually play a small role in the eventual defeat of the Night King. In both the first book and the first season of Game of Thrones, Arya Stark's Swordmaster, Syrio Forel, gives her the task of chasing and catching cats as part of her training.

Syrio's reasoning for this is that cats can often move about without attracting attention, and if Arya can learn to do the same, her swordwork, and Arya herself, will be better off for it. Arya is skeptical, but respects Syrio enough to do as he asks.

The training pays off years later, as when the Long Knight arrives. Arya is able to use her skills to sneak past the army of White Walkers unnoticed, arriving in time to save her brother, Bran, and ultimately killing the Night King, saving all of Westeros from an icy fate.

In the television universe, it seems Rhaenyra will be the one to release cats into the Red Keep, so in some small way, she contributes to the Song of Ice and Fire, just as her Father wished.