House of the Dragon fans were left wondering who the mysterious woman was who appeared in Daemon's dreams, but now her identity has been revealed.

*Warning - The following article contains spoilers from House of the Dragon season 2, episode 4 and major spoilers from George R.R. Martin’s Fire and Blood.*

The House of the Dragon fandom last week was abuzz with curiosity over an engaging woman in the ruins of Harrenhal castle who chillingly warned Daemon Targaryen: "You will die in this place."

HBO viewers have now seen her identity unveiled in episode 2, season 4. The mysterious character, played by Gayle Rankin, is none other than Alys Rivers.

Repeatedly appearing central to Daemon's terrifying dream sequences, it is a young version of his wife Rhaenyra Targaryen (Milly Alcock) who takes centre stage. She challenges his defiant stance as her claim to the throne continues to be thwarted.

Daemon's allegiance sways between loyalty towards Rhaenyra and the part of himself arguing he is a better candidate for the throne. In the latest offering, he meets with Alys and they share a conversation that sheds light on his inner-most thoughts.

The revelation that she comes from "illegitimate" roots, with Strong as her actual surname rather than Rivers, coupled with her apparent healing skills makes her even more intriguing. Want to know more about Alys? Keep reading but - be warned - spoilers ahead.

What does Alys Rivers say to Daemon?

In the third episode, Alys tells Daemon that she has foreseen his demise within the walls of Harrenhal castle.

Fast forward to episode four, she introduces herself formally to the prince, throwing light on her knowledge of his nightmares.

"How are you settling in? I've come to know the face of tortured rest well enough. Sleep can be thin in this place," she nudges him.

"What would you know of my sleep? " Daemon fires back, only for Alys to tease the possibility that life at the castle could seep into his dreams.

"Harrenhal's been cursed since its first stone was laid," she says. "Black Harren felled the grove of Weirwood trees that grew on these lands.

"Heart trees, imbued with the spirits of those who lived long before he came. It's said their whispers can still be heard sometimes."

While Daemon dismisses her warning as a "midwife's tale", he looks less sure once she tells him the bed in which he sleeps is made from one of the trees.

Later, Alys queries Daemon on whether he has quarrelled with Rhaenyra, pointing out: "You arrive here alone, claim the castle, and yet send no ravens.

"Do you now plan to make your own claim? Perhaps to prove yourself to her?"

Daemon grows irritable and calls her a witch, but she persists, saying: "It's a hard thing, I imagine, to give obeisance to one who replaced you as heir. And a woman, too."

Alys then gives Daemon an unknown concoction to help him sleep so he can "win this place to your side" and he appears to awaken from his dream-like state moments later.

Did that whole scene really happen? Or has Alys found a way inside Daemon's head?

Who is Alys Rivers and what happens to her in the books?

Alys Rivers is a healer and resident of Harrenhal. She is also an important character to watch out for as the Dance of the Dragons kicks off.

In George R. R.Martin's prequel book to the Game of Thrones story, Fire and Blood, she plays a huge part in the Civil War.

In the novels, Alys serves as a child nurse for the House Strong family in Harrenhal and is gifted with visions of the future.

When Aemond Targaryen and Ser Criston Cole seize Harrenhal in the name of Aegon II, Aemond orders the execution of House Strong members who had aided Daemon.

However, he spares Alys' life and they become lovers, resulting in her becoming pregnant with Aemond's child.

When Daemon returns to Harrenhal to battle Aemond, Alys witnesses both men plummeting to their deaths in Gods Eye lake.

She then vanishes until the civil war concludes, later seizing control of Harrenhal with a band of outlaws and asserting that her son is the rightful heir to the throne.