Viewers of House of the Dragon have eagerly anticipated greater intensity from the Game of Thrones prequel on HBO and that moment may arrive sooner than many expect.

Before the third season debut this Sunday showrunner Ryan Condal has highlighted the Battle of the Gullet which the book Fire and Blood calls one of the most violent sea fights in the history of Westeros.

Condal explained to Entertainment Weekly that omitting this event would be like adapting Lord of the Rings without the Battle of Helms Deep. He stressed that doing it properly required dragons ships and several areas of fighting at once.

He added that the sequence ranks as arguably the most ambitious episode of television ever produced when considering its cost and complexity.

Followers of George R. R. Martins universe are familiar with grand spectacles and combat such as the fiery end of Princess Rhaenys Targaryen in season two the Battle of the Bastards or the numerous foes burned by Daenerys Targaryen.

Yet the Battle of the Gullet involves more than lavish production values and effects. It marks a pivotal shift in the Targaryen civil war known as the Dance of the Dragons and carries major weight for the future of the family line.

Below is a summary of the naval and dragon confrontation from the novel with spoilers for Fire and Blood and possible developments in season three.

A new threat was closing from the east

The clash unfolds in 130 AC less than a year after Aegon II Targaryen took the crown ahead of his half sister Rhaenyra the designated successor. AC refers to years after Aegon I united the realm.

Rhaenyras advisors gather on Dragonstone under the direction of her son Prince Jacaerys while her husband Prince Daemon assembles forces at Harrenhal.

As Jace prepares an assault on the capital enemies arrange a surprise attack from the sea.

Aegons supporters have allied with the Triarchy whose combined fleets hail from three free cities in Essos.

The Triarchy had previously clashed with Lord Corlys Velaryon over the Stepstones islands. Their ninety warships aim to end the blockade that starves Kings Landing of supplies.

While approaching the Gullet the fleet encounters the Gay Abandon carrying Rhaenyras younger sons Aegon III and Viserys II who were sent to safety by Jace with seven escort ships.

The Triarchy destroys the escorts and seizes the vessel. Nine year old Aegon escapes on his dragon Stormcloud and reaches Dragonstone but the dragon suffers fatal arrow wounds during the flight.

Seven year old Viserys lacks an escape option since his dragon egg remains unhatched and is taken by admiral Sharako Lohar.

It is one thing to face a dragon another to face five

Alerted by the warning Jace rides Vermax into battle. Four additional dragonriders soon join including Ulf on Silverwing Addam on Seasmoke Hugh on Vermithor and Nettles on Sheepstealer. The show appears to assign Nettles role to Rhaena Targaryen.

Rhaenyra herself stays out of the fight in the novel. Sources suggest grief over Lucerys death or caution from advisors keeps her from participating.

All seemed lost all was lost

The Triarchy sacks Driftmark yet their ships scatter under attack from five dragons. Vessels explode or burn with crews leaping into the sea amid rising smoke.

Vermax plummets after being struck and Jace leaps free only to be felled by crossbow bolts from enemy vessels.

The fight lasts into the night leaving just twenty eight Triarchy ships intact. Though Corlys claims victory the cost to Driftmark and the loss of Jace renders it hollow. He remarks that if this counts as victory he hopes never to claim another.

Jaces death hardened her

The outcome disrupts Rhaenyras succession plans and deepens her personal losses. Aegon III returns traumatized while Viserys is feared dead.

Historians in the book note that the battle strips Rhaenyra of her former grace turning her toward ruthless vengeance and a vow to bring fire and death to her foes.

Broken by one sons loss she gains new resolve from the second. Jaces death steels her resolve burning away fear and leaving only anger and hatred.