Alys Rivers (Gayle Rankin) has been keeping quite the big secret at Harrenhal all these years!

In this week’s all-new House of the Dragon on HBO, Alys finally lays all her cards on the table to seduce a rather aloof Aemond Targaryen (Ewan Mitchell). When it seems that nothing will woo him to her cause, she reveals a rather insane treasure that she’s kept hidden for a long time…

**Spoilers for House of the Dragon Season 3 Episode 6, now streaming on HBO Max**

Alys takes Aemond to a storeroom and reveals a cache of five dragon eggs. Not only that, they come from a rather important dragon: Dreamfyre.

“Your ancestor Rhaena Targaryen came to Harrenhal after the death of her daughter. And she grieved and grew old here,” Alys says. “Her dragon laid a clutch of eggs before Rhaena herself died and they have sat here, cold and abandoned these hundred years.”

Alys then makes the big pitch: Aemond should stay at Harrenhal with her and she will the “Lady of the Water” and he will be her “dragonlord.” Their sons will be Targaryen princes, riding the dragons that Aemond helps her hatch from these otherwise petrified eggs. In fact, Aemond’s mere presence seems to wake one of them. She says the eggs are “cold,” but he feels warmth.

So what’s the big deal with Dreamfyre’s eggs being at Harrenhal? Who was the original Rhaena Targaryen — not to be confused with our Rhaena, who rides Sheepstealer and is played by Phoebe Campbell — and why is she a fan favorite? And how does this connect or change things from the books?

Here’s everything you need to know about Dreamfyre’s eggs at Harrenhal…

How Did Dreamfyre’s Eggs Wind Up at Harrenhal in House of the Dragon? Who Was the Original Rhaena Targaryen?

According to Alys Rivers, the dragon Dreamfyre laid five eggs at Harrenhal when the original Rhaena Targaryen lived there after the death of her daughter.

The first Rhaena Targaryen is one of the most fascinating characters in George R.R. Martin’s Fire & Blood. She’s the granddaughter of Aegon the Conqueror and his beloved sister-wife Rhaenys. After her father, Aenys I died, she and her (dragon-less) teenaged brother Aegon were supposed to be next in line, but their vicious uncle Maegor the Cruel took King’s Landing instead. Aegon and Rhaenys’s next youngest brother were both killed, while her mother, Alyssa Velaryon essentially hid with her younger children, Jaehaerys and Alysanne.

Maegor was obsessed with producing an heir. So his first three wives had trouble having a healthy baby, he married three widows who had already had children. One of these “Black Brides” was none other than Rhaena herself. (She and dead Aegon had twin daughters, Aerea and Rhaella.) For whatever reason, people believe that Rhaena ultimately had a hand in killing Maegor. He was mysteriously discovered impaled on one of the blades on the Iron Throne, while she had snuck away with the sword Blackfyre as a gift for her youngest brother Jaehaerys.

While her siblings became King Jaehaerys the Wise and Queen Alysanne the Good, Rhaena married Androw Farman, a pretty, but dumb and useless knight. In fact, it seems that the reason she wed him was to be close to his sister Elissa Farman. Eventually, the two women would settle on Dragonstone with Aerea, but Elissa — a great sailor — grew restless. She stole three eggs laid by Rhaena’s dragon, Dreamfyre, and used them to fund her expedition to the other side of the world. (Many fans suspect these three stolen eggs eventually found their way to Dany in the main series.)

Aerea became something of a problem child, desperately wishing to leave Dragonstone for King’s Landing. One day, she claimed Balerion the Black Dread — aka Aegon the Conqueror’s dragon — and flew away. Rhaena spent ages searching for her daughter, who eventually arrived home utterly changed. She was tremendously ill, with an insanely hot fever and creepy crawlies wiggling under her skin. Aerea died. The understanding is that Balerion took her to Old Valyria, where she was infected by whatever still lived there after the Doom.

A devastated Rhaena withdrew to the widow’s tower of Harrenhal to live out her days. She lived there an additional 17 years, grieving her daughter, riding her dragon, and even running the household after her original host died.

It seems that during her time there, Dreamfyre laid one last clutch of eggs. Considering that no one knows for sure if Alys Rivers is just a clever young woman with mystical knowledge or an immortal witch… Did Alys know Rhaena??

Why is Dreamfyre One of the Most Important Dragons?

Besides being Rhaena’s super cool dragon and the mother of many, many dragon eggs, Dreamfyre is still kicking around during House of the Dragon.

Dreamfyre’s current rider is none other than Helaena Targaryen (Phia Saban), though she prefers to stay on the ground and let Dreamfyre hang out in the Dragonpit.

Both of Dreamfyre’s riders started off as shy girls and grew stronger after they claimed Dreamfyre. Rhaena became a force of nature and a strangely intuitive dragon handler. Legend has it that she is the Targaryen who began the tradition of putting dragon eggs in cradles. Helaena, on the other hand, is a Dreamer on the HBO show.