Here's why Rhaenyra Targaryen may become queen in 'House of the Dragon' season three

• Rhaenyra Targaryen has been gunning for the throne in "House of the Dragon" after her half-brother usurped her.
• At the end of season two, she hatches a plan that could finally put her on top.
• Here's how she becomes queen in "Fire and Blood," the book the show is based on.

Warning: Major spoilers ahead for "House of the Dragon" season two finale and the book "Fire and Blood."

Rhaenyra Targaryen and her biggest rival, Alicent Hightower, form a pact to take over the kingdom in the "House of the Dragon" season two finale. They may succeed if the series follows the George R. R. Martin novel on which the show is based.

Rhaenyra (Emma D'Arcy) was the initial heir to the throne after her father, King Viserys I (Paddy Considine), died in season one. But Alicent (Olivia Cooke) thought she heard him change his mind and didn't trust Rhaenyra, so she propped up Aegon (Tom Glynn-Carney), her eldest son with Viserys, to be the next king.

In season two, Rhaenyra has been plotting a way to win back the throne without endless bloodshed. When this proves fruitless, she prepares for full-blown war in the season two finale.

Then Alicent arrives, offering a plan to help Rhaenyra take over the capital, King's Landing, in exchange for the safety of herself and her daughter Helaena (Phia Saban). Alicent just wants to escape the kingdom with her daughter and even asks Rhaenyra to come with her, but Rhaenyra declines.

As for Alicent's two sons who oppose Rhaenyra, Alicent agrees for Rhaenyra to execute her eldest, Aegon, but there is no plan yet for Aemond (Ewan Mitchell) and his massive dragon, Vhagar.

Unfortunately, we don't see this plan in motion. The series leaves it as a major cliffhanger to keep fans eager for the next season.

But if you don't want to wait, here's how Rhaenyra takes over the throne in Martin's "Fire and Blood."

Rhaenyra takes over King's Landing without Alicent's help in 'Fire and Blood'

In the book, Aemond, Vhagar, and Criston Cole leave King's Landing with a big army to fight Daemon, Rhaenyra's husband, in the Riverlands and reclaim the fortress Harrenhal.

Instead of facing them, Daemon left Harrenhal with his dragon Caraxes. He and Rhaenyra took over King's Landing with their dragons, their team of dragonriders, and a fleet led by Corly Verlaryon.

All messengers were cut off before they could send out a call for help, and Alicent's brother, Ser Gwayne Hightower, was also killed in the chaos.

Alicent eventually surrendered the capital, but Aegon II, his daughter Princess Jaehaera, and his son Prince Maelor fled with Larys Strong.

But when Rhaenyra finally sat on the Iron Throne, the book said that the throne cut her hand. This was an omen that the throne had rejected her, and she would not be queen for long.

Ser Otto Hightower and Lord Jasper Wylde were later executed, Ser Tyland Lannister was tortured, Alicent and Helaena were imprisoned.

Meanwhile, Aemond and Criston Cole conquered Harrenhal easily, but they separated when they heard of Rhaenyra's plot. Aemond continued to burn the Riverlands, hoping Rhaenyra's dragons would come after him, while Criston Cole went with his armies south to join the rest of the armies against Rhaenyra.

"House of the Dragon" seems to be already changing the events of this part of the story. Alicent has betrayed the Greens, offering King's Landing on a silver platter to Rhaenyra. The question remains whether Rhaenyra will honor her word and let Alicent go free or capture her.

Otto Hightower and Tyland Lannister are nowhere near King's Landing, so they may escape their grim fates. Finally, Aegon and Larys appear to have left Jaehaera behind when they fled the capital in the season two finale.

The fall of King's Landing will likely not play out the same as in the book.

Rhaenyra rules from King's Landing for most of the rest of the war

After this major shift in the war, Rhaenyra ruled for less than a year, but it was not an easy rule.

Aegon and Aemond still oppose her rule and have not been captured. Daeron, Alicent's third brother, and Lord Ormund Hightower have an army and a dragon in the south that is slowly making its way to King's Landing.

Rhaenyra struggled to raise enough money to look after King's Landing because most of the gold had been sent away.

Then, two of Rhaenyra's dragonriders, Hugh Hammer and Ulf White, switched sides and betrayed Rhaenyra, taking their dragons, Vermithor and Silverwing, with them. Rhaneyra then questioned the loyalty of the other two riders, Nettles and Addam, and called for them to be arrested, but both escaped.

Corlys Velaryon was arrested for helping Addam escape, and most of his fleet fled.

The final straw was when Helaena died by suicide, promoting whispers that she had been murdered and inspiring a riot calling for justice.

Some men took advantage of the riot, with bastards claiming they should rule instead and other groups who went to the dragon pit to kill the dragons.

Rhaenyra's son Joffrey rode on Syrax to save the other dragons, but he fell off and died. Then Rhaenyra and her remaining son, Aegon the Younger, fled the castle.

Rhaenyra never rules again after this and is later murdered by her half-brother Aegon using his dragon Sunfyre. Since most of the key players had died at this point, there were only a few more battles after Rhaenyra's death.

It is unclear whether "House of the Dragon" will follow this storyline in its entirety or take a different direction. Fans will have to wait until the next season premieres.