Gayle Rankin as Alys Rivers in "House of the Dragon" season three.
Ollie Upton/HBO
Warning: Spoilers ahead for "House of the Dragon" season three, episode five, and for the book "Fire & Blood."Alys Rivers may not be a dragonrider or a soldier, but the self-proclaimed "barn owl cursed to live in human form" is one of the most formidable figures in "House of the Dragon."Portrayed by Gayle Rankin, Alys is introduced in the HBO show's second season as the unofficial maester of Harrenhal, a derelict castle in the Riverlands held by House Strong. Alys' job is to tend to the noble men within its walls (or whatever's left of them).However, despite her low status, Alys is quickly revealed to be more of a puppet master than a simple servant.Once Daemon Targaryen (Matt Smith) arrives with his dragon to claim Harrenhal, he finds an unlikely ally in Alys. During his time in the castle, Alys gives Daemon potions that seem to induce powerful visions. Using her mysterious influence, she guides the so-called "Rogue Prince" through his doubts, fears, and regrets, culminating in the epiphany that he's not destined to rule. By the end of the season, Daemon has returned to his wife, Rhaenyra Targaryen (Emma D'Arcy), rallied an army in her name, and vowed to help her seize the Iron Throne.Although Daemon and Alys seem to form a bond, she keeps her true agenda obscured until season three."I've done the queen a service. I put 40,000 Rivermen at her call," she tells Daemon in season three's second episode, titled "Queen's Landing."
