Alicent heads to Harrenhal in House of the Dragon’s risky new twist

House of the Dragon is sending Alicent Hightower to Harrenhal, and the Alicent Harrenhal House of the Dragon twist may be the HBO drama’s boldest break yet from George R.R. Martin’s Fire and Blood, according to Mashable’s analysis of Season 3.

The move puts Olivia Cooke’s Alicent far from her usual Red Keep setting and into the orbit of Aemond Targaryen, played by Ewan Mitchell. Mashable reports that the storyline is built around an assassination plan aimed at Aemond while he is at Harrenhal and away from Vhagar, his dragon.

The plan, as described by Mashable, comes from Rhaenyra Targaryen. She knows Aemond is vulnerable without Vhagar, but she also believes sending a large force could drive him into hiding again. Her answer is smaller and sneakier: send one blade, with Alicent alongside as the familiar face meant to lower Aemond’s guard.

Why is Alicent going to Harrenhal?

Alicent is being used as part of Rhaenyra’s attempt to get close enough to Aemond for an assassin to kill him, according to Mashable. The show’s logic is that Aemond may trust his mother enough to let danger get near him.

That is a major change from Fire and Blood. Mashable notes that in Martin’s book, Alicent stays in the Red Keep after Rhaenyra takes the Iron Throne, so there is no direct book version of this Harrenhal mission to follow.

Season 3 has already been making big changes to Martin’s material. Mashable points to Ormund Hightower’s plan to crown Daeron Targaryen as a show-created plot, and to the decision to give Nettles’ book storyline to Rhaena Targaryen, played by Phoebe Campbell.

Alicent’s trips outside the Red Keep have become a sign that the series is leaving the page behind. Mashable notes that, starting in Season 2, her major exits from the Red Keep were not in Fire and Blood: meeting Rhaenyra in the Grand Sept to discuss peace, taking a swim in the Kingswood, and sneaking to Dragonstone to offer Rhaenyra a deal.

The show has long reworked Alicent and Rhaenyra’s relationship by making them childhood friends, a choice Mashable says complicates their book dynamic. That change helps explain why Alicent keeps being pulled into personal, risky missions that do not exist in Martin’s history-style account.

What could Alys Rivers do?

Alys Rivers, played by Gayle Rankin, is the obvious complication at Harrenhal. Mashable describes her as the witchy guardian of the castle, a figure who has already drawn in Aemond by using his mother issues and showing him dragon eggs.

Mashable also notes that Alys has shown awareness of events beyond Harrenhal, including knowledge of the Battle of the Gullet in Season 3’s first episode. That makes Alicent’s secret purpose dangerous before the plan even starts.

The biggest unknown is Alicent herself. Mashable frames her as someone who understands Aemond’s volatility and wants to protect Helaena, while also facing the possibility of helping kill one of her own sons.

With no book roadmap for Alicent at Harrenhal, the show has left viewers with a high-risk detour and no tidy answer. House of the Dragon Season 3 is streaming on HBO Max, with new episodes premiering Sundays at 9 p.m. ET on HBO and HBO Max.

This story draws on original reporting from Mashable.