'House of the Dragon' Blood and Cheese Storyline: Everything to Know (Including What's Changed From the Book)

'House of the Dragon' introduced a brutal development in the war between the Blacks and the Greens in Sunday's season 2 premiere.

Warning: Spoilers ahead for the House of the Dragon season 2 premiere, "A Son for a Son." 

House of the Dragon kicked off its second season in gut-wrenching fashion. 

Fans of George R.R. Martin's Fire & Blood -- which serves as the inspiration for HBO's Game of Thrones prequel -- didn't have to wait long to see one of the most eagerly anticipated plot points of season 2: "Blood and Cheese." The grotesque storyline was tackled head on during Sunday night's premiere episode. 

Following the horrific death of Lucerys Velaryon -- the second son of Queen Rhaenyra (Emma D'Arcy) -- in the season 1 finale, a thirst for vengeance is in the air. Prince Daemon (Matt Smith) -- Rhaenyra's uncle-turned-current husband -- takes it upon himself to enact revenge. In short, Daemon hires a pair of assassins nicknamed "Blood" and "Cheese" to sneak into the palace and slay Prince Aemond (Ewan Mitchell) for killing Lucerys with his dragon. 

"You're to find and slay the Prince Aemond Targaryen," Daemon says. "He has silver hair and one eye. Should be easy enough to find." 

Ewan Mitchell as Prince Aemond Targaryen in 'House of the Dragon' - Ollie Upton/HBO

He adds, "But I understand he's quite good in a fight. You'll want to take caution." 

Daemon then offers a sack full of money as half payment, promising to pay the second half "when it's done." 

Cheese then asks, "What if we can't find him?" 

Daemon does not appear to respond, simply staring back at him with a sinister look. 

In the next scene, Aemond is seen talking strategy with Ser Criston Cole (Fabien Frankel). They are interrupted by Aemond's grandfather and the Hand of the King, Otto Hightower (Rhys Ifans). 

'House of the Dragon': Fabien Frankel as Ser Criston Cole and Ewan Mitchell as Prince Aemond Targaryen. - HBO

Blood, a disgraced swordsman, and Cheese, a rat catcher, then embark on their journey through the Red Keep with a small dog in tow. The duo unwittingly find themselves in front of the Iron Throne, where a drunk King Aegon II (Tom Glynn-Carney) is gossiping with his friends. The group is so inebriated, Blood and Cheese walk right by them undetected before losing their way in the castle. 

Tensions rise as Blood and Cheese realize they don't know where to go, with Cheese viciously kicking his four-legged companion aside as they continue on their mission through the royals' private upstairs residences.

When Blood says they "need to keep looking," Cheese becomes frustrated and snaps, "I told ya, I'm not supposed to be up here." 

Blood reminds him, "No head, no gold." The duo then go their separate ways as Cheese creates a distraction by setting a rat trap and Blood continues to explore. At one point, he comes across one of the handmaids. Blood explains his presence simply by saying, "For the rats," and spares her life as he walks away. 

Cheese then hears a commotion and moves to another room, where he finds Queen Helaena (Phia Saban) -- the sister-turned-wife of King Aegon II. When Blood finds them, Cheese is holding the Queen with a knife to her throat. 

"A son for a son," Blood reminds Cheese. "Does she look like a f**king son to you?" 

Then, Cheese gestures to the matching beds where Helaena and Aegon's two young children are asleep. 

'House of the Dragon': Phia Saban as Queen Helaena - HBO

The assassins struggle to identify which child is male, asking Helaena to point him out. The Queen attempts to offer them her necklace instead, eventually conceding and tearfully pointing to her sleeping son. 

Blood initially doubts that Helaena is being truthful, suggesting that she wouldn't "give up the King's heir that easy." Cheese, looking deep into her eyes, says, "No, she's telling true." 

The disturbing scene concludes with Blood and Cheese violently holding down the tiny Prince Jaehaerys Targaryen as the camera pans away to a distressed but stoic Helaena grabbing her daughter and fleeing the room. The imagery is set against the chilling sounds of Jaehaerys' cries silenced by beheading. 

Helaena makes her way to the room of her mother, Queen Alicent (Olivia Cooke), who is amid the throes of passion with her secret lover, Ser Criston Cole (Fabien Frankel). 

"They killed the boy," Helaena says simply. 

Meanwhile, Aemond, the assassins' intended target, lives to see another day. 

Olivia Cooke as Alicent Hightower in HBO's 'House of the Dragon' - Ollie Upton/HBO

Showrunner Ryan Condal told ET at the series' New York City premiere on June 3, "We're being true to the story that's written in the book."

However, unlike GOTHouse of the Dragon's source material is written not as a narrative, but as a scholarly document penned by Archmaester Gyldayn, including an unreliable narration of historical events from a cast of varying sources. The style of Martin's telling has allowed show writers plenty of room for creative liberties, expanding throwaway details into fully formed plots, developing characters and relationships, and even inventing jaw-dropping new scenes over the last season. 

Prior to Sunday's episode, many book readers had speculated how the show could deliver Jaehaerys' gruesome death in a way that wouldn't traumatize child actors -- or viewers. The answer, apparently, was to rely on the stomach-churning backing track of grunts, squelching and sawing rather than on-camera visuals. 

Meanwhile, the show did appear to make some other changes from Martin's book. Among the most notable of them is Daemon's original intention. 

According to multiple accounts, including the Fandom site Villains Wiki, the book version of "Blood and Cheese" found Daemon specifically asking for one of Aegon's two sons -- not Aemond -- to be killed.

In the book, Blood and Cheese make their way straight to Alicent's chambers, where they hold the Dowager Queen hostage and kill her handmaid. They wait for Helaena to bring her children to the room to say goodnight before heading off to bed. 

In the end, they force Helaena to choose which of her sons should die. She bargains unsuccessfully, asking them to take her life instead. Eventually, under threat of death for all three of her children -- including her daughter, Princess Jaehaera -- she tearfully chooses the youngest son, Prince Maelor, to be killed. Cheese then taunts the boy, telling him his mother wants him dead, while Blood cuts off Jaehaerys' head instead.

The traumatizing incident appears to serve as the spark that drives Helaena into insanity. On the show, however, her character has long been portrayed as, in Aegon's words, "an enduring mystery." 

As for what's next, a new episode of House of the Dragon will air Sunday, June 23, on HBO. 

RELATED CONTENT: