We're now well into the long night between seasons of House of the Dragon, and what better way to while away the days than by revisiting Fire & Blood, the fictional history novel by George R.R. Martin that explores the first 130 or so years of House Targaryen's reign over the Seven Kingdoms.
The deeper we get into House of the Dragon, the more pronounced its differences from Martin's book become. Characters have completely different motivations, storylines, and interactions, some events are emphasized more or less than others, and many of the book's political schemes play out in totally different ways. This is especially true when it comes to character deaths; some key figures who are still alive in the show are long dead by now in the book, while others died much earlier in HBO's adapation.
As I've been going back through a close read of Fire & Blood, a few of those book deaths stand out. In particular, there are three knights who are all dead by the end of House of the Dragon season 3 who meet their demise in the book at crucial events which have yet to happen in the show. These events are central to the story, meaning we are all but certain see them in House of the Dragon. But without the knights in question, the chances are very good they'll play out in an entirely different way on screen.
MAJOR SPOILERS for Fire & Blood beyond this point.

Ser Luthor Largent will never face the Shepherd
House of the Dragon season 3 leaves off on the somber note that Rhaenyra Targaryen (Emma D'Arcy) has fully descended into her villain era, while her half-sister Helaena (Phia Saban) leapt from a window to her death. In the book, Helaena's death is the spark which sets King's Landing ablaze; the very night that she dies, the smallfolk rise up in bloody riots, plunging the city into chaos. This is the result of long-simmering problems in the capital, such as the crown's oppressive taxes and Rhaenyra's order to lock the gates of the city after being betrayed at the First Battle of Tumbleton, trapping all its residents inside because of her paranoia that another attack is imminent.
Word of Helaena's death spreads fast, and several malicious actors seek to twist it to their own ends. Larys Strong is hidden in the city, and he takes full advantage of the situation to damage Rhaenyra's reputation. But the worst is a barefoot, one-armed zealot called the Shepherd, who preaches that all the Targaryens and their dragons must be killed to free the Seven Kingdoms from self-destruction. He was already gaining crowds before Helaena's death; the night that she perishes, more than 10,000 souls turn out to hear him preach the downfall of House Targaryen.
Obviously, Rhaenyra cannot let this stand. She sends the captain of the gold cloaks, Ser Luthor Largent, out with his men to disperse the crowd. But Luthor's group of a few hundred stands no chance against a mob of 10,000. They are overcome, swarmed by the peasants and bludgeoned or stabbed to death. This marks a true turning point in the city, where it becomes clear to both the smallfolk and Rhaenyra that the queen has lost control, and the people have gained it.
After Luthor's death, the smallfolk go on a rampage throughout the city. This builds their confidence, and the following night, an even more horrific event known as the Storming of the Dragonpit happens, which spells the end for Rhaenyra's reign over King's Landing.

In House of the Dragon, Luthor (Tom Cullen) dies in season 3 episode 5, when he and the rest of the gold cloak leadership are assassinated by Ormund Hightower's (James Norton) agents in the capital. This ultimately serves a similar goal, with the people losing faith in the gold cloaks and Rhaenyra's grip on the city waning, but by killing Luthor so much earlier, it means we won't see his death during the riots, which happens at a time in the novel when he's a much more substantial figure who's known to the smallfolk.
The riots in King's Landing are all but certain to be a major part of season 4. In the book, it's a complex, bloody affair with many moving parts. By cutting off Luthor's story early, House of the Dragon has removed one facet of the riots, meaning we already know it will happen somewhat differently than Martin's novel.

Ser Lorent Marbrand will not face the mob
The riots in King's Landing go through a natural ebb and flow. The morning after the brutal events which claim the lives of Ser Luthor, his gold cloaks, and so many others, Rhaenyra and her allies try to ressert control over the city. Several parties of soldiers and knights are dispatched on different sorties around King's Landing, in the hopes of preventing even more horrors on the following night.
They fail utterly. While Rhaenyra's allies are repelled at pretty much every turn, those who suffer the worst are a group of 100 knights led by Ser Lorent Marbrand, the Lord Commander of the Queensguard. These valiant men go into Flea Bottom, where the unrest is the worst. Of those 100 knights, only 16 make it back, and as Martin writes, "Ser Lorent, Lord Commander of the Queensguard, was not amongst them."
Lorent's death is the beginning of the end for Rhaenyra's Queensguard. She names another young knight, Ser Glendon Goode, as the new Lord Commander, but he only lasts two days in the role before he dies as well. Four members of the Queensguard do manage to defend Rhaenyra long enough to eventually escape the city, but their days are numbered and the order will never again reach a full seven.
As of right now, Ser Glendon hasn't yet been introduced in the show. There's a very cool aspect to his story where he leads six other knights on a daring mission into the city, which earns them the name the Seven Who Rode. It's still entirely possible that House of the Dragon could introduce Ser Glendon in its final season, but as things stand the jury is very much out on whether the King's Landing riots will include this piece of Martin's book.
In House of the Dragon, Ser Lorent Marbrand is executed off screen for his part in preventing Rhaenyra Targaryen from going to the Battle of the Gullet, which leads to the death of her son, Jace (Harry Collett). It's an ignominious end for a knight who serves her faithfully and truly throughout the entirety of the novel.

Ser Adrian Redfort will not witness Rhaenyra's "last and most grievous treachery"
The last knight who won't meet his end as he does in the book is Ser Adrian Redfort (Barry Sloane), Rhaenyra's new Queensguard member who was introduced in season 3. Ser Adrian doesn't play an especially large role in either the show or the book, so this one stands to impact the story the least. However, it's still fascinating to look at how differently he met his fate in these two different versions of the Dance of the Dragons.
In the show, Ser Adrian goes with Alicent Hightower (Olivia Cooke) to Harrenhal in hopes of assassinating her son, Aemond. They try to pull a ruse on Aemond, but to their surprise, the one-eyed Targaryen prince promptly stabs Adrian to death. In a darkly hilarious turn, Aemond wasn't even suspicious anything was amiss; there were simply secrets at Harrenhal he didn't want this unknown knight to witness.
In Fire & Blood, Ser Adrian Redfort is one of Rhaenyra Targaryens last living defenders. After the Black Queen is driven from King's Landing, Ser Adrian guards her all the way back to Dragonstone, where she hopes to find safety after a dangerous journey across the Crownlands. But there, the queen meets with a terrible surprise: her brother, Aegon II, has already taken control of the island with the help of Ser Alfred Broome, an older knight Rhaenyra slighted when she passed him over for a promotion.
The second Rhaenyra realizes she's walked into a trap, Broome's soldiers spring into action and murder the warriors in her entourage. That includes Ser Adrian Redfort and the last three other members of the Queensguard. After that, Rhaenyra is well and truly defenseless as she's brought face-to-face with Aegon at last.
Realistically, House of the Dragon can absolutely still do this plot beat without Ser Adrian Redfort. The show essentially swapped one death scene where he's caught totally unawares for another. But it's still interesting to see that all of Rhaenyra's named Queensguard knights in House of the Dragon have already perished, leaving a question as to how the end of these elite guardians will be handled in the show's final season.

Two surviving knights could still change House of the Dragon's endgame
While we've talked about several knights who died earlier than their book counterparts in House of the Dragon, there are a few instances where the opposite is true as well. The most important example is Ser Gwayne Hightower (Freddie Fox). Gwayne dies in the book when Rhaenyra takes King's Landing, murdered by Ser Luthor Largent and the other gold cloak traitors when they switch sides to throw in with the queen. House of the Dragon has given him a much more substantial story arc, which sees him go on a doomed campaign with Ser Criston Cole (Fabien Frankel) in the Riverlands before he ends up at Tumbleton, just in time for the first horrific battle there.
Gwayne survived season 3, and now that he's essentially the heir to House Hightower following the death of Ormund, it's all but assured House of the Dragon will have some bigger plan for him in its final eight episodes. Of all the knights on this list whose stories deviated from Fire & Blood, Gwayne is the one House of the Dragon has gotten the best mileage from.
The other knight who may turn up in season 4 is Ser Rickard Thorne (Vincent Regan), a loyal Kingsguard of the Greens. We last saw Ser Rickard being carted off to the dungeon after a standoff with Rhaenyra and Daemon in the Iron Throne room during the season's second episode. In the book, Thorne escapes during the Fall of King's Landing; he later dies at a town called Bitterbridge, defending Aegon and Helaena's youngest son, Maelor.
Since Maelor has essentially been cut from the show, House of the Dragon could do anything it wants with Ser Rickard Thorne. Most likely, he'll remain in the dungeon until Rhaenyra is driven from the city. After that, there's a period of chaos in King's Landing where one of the would-be peasant kings who exerts control over a portion of the city decides to release many of the queen's captives. Perhaps Ser Rickard will be among them in the show's version of events?
Knights have always been a key part of George R.R. Martin's Westeros, and these five all have parts to play in the Dance of the Dragons, big and small. While House of the Dragon has charted a different course for each of them, we'll only truly find out how these changes effect the overall narrative once season 4 releases. Until then, there's always more time to read Fire & Blood.
House of the Dragon season 4 is set to begin pre-production later this fall, and start filming in early 2027. Look for it to premiere sometime in 2028.
