What book is House of the Dragon based on — and how much of it is left to adapt?
House of the Dragon — whose third-season finale aired on HBO 9 August 2026 — is adapted from Fire & Blood, George R.R. Martin's 2018 fictional history of House Targaryen. Not a novel: a history book, written in the voice of a maester piecing together contradictory sources about events 150 years before Game of Thrones.
That framing matters more than you'd think — and it's why the question of how much is "left" has two answers.
The book, briefly
Fire & Blood runs from Aegon's Conquest of Westeros through to the regency of the boy king Aegon III — roughly a century and a half of Targaryen rule, in about 700 pages. House of the Dragon adapts only the middle stretch: the Dance of the Dragons, the Targaryen civil war between Rhaenyra and Aegon II. Because the "history" is told through unreliable chroniclers who disagree with each other, the show's writers have unusual room to pick a version — or invent one.
How much has been used so far
- Season 1 (2022) — the long build-up: succession politics, marriages, and the death that starts the war.
- Season 2 (2024) — the opening moves of the Dance itself, ending just before the fighting escalated.
- Season 3 (2026) — eight episodes, 21 June to 9 August, covering the war's biggest set pieces: the Battle of the Gullet in the very first episode, Rhaenyra taking King's Landing, and Tumbleton.
Martin himself has grown publicly unhappy with the adaptation's growing distance from his text. In a post on his Not A Blog — titled "Beware the Butterflies" — he warned of
"larger and more toxic butterflies to come" if the show pressed ahead with changes planned for seasons 3 and 4.
The Ringer spent this season asking whether the show still counts as an adaptation at all. HBO has not adjusted course.
What's actually left
Season 4, confirmed in August 2024 as the final one, covers the Dance's last act and its aftermath — which, in the book, includes the downfall of several of the biggest names still standing. Scripts have been in the works since January 2026, filming is expected to start in early 2027, and the season should arrive around 2028.
And the rest of the book?
Untouched. The Dance is only Fire & Blood's middle third — Aegon's Conquest, the reigns before Viserys, and everything after the regency remain available for other projects. Fire & Blood is also billed as volume one of two; Martin hasn't finished the second.
The show, in other words, will end with most of its source material still on the shelf.