The narrative of House of the Dragon, an adaptation of George R.R. Martin's Fire & Blood, has not shied away from brutal character deaths. As the series progresses through the events of the Dance of the Dragons civil war, further casualties are anticipated. Queen Helaena Targaryen, daughter of Alicent Hightower and Viserys Targaryen, and wife to Aegon Targaryen, faces a particularly poignant end.
According to "The Dying of the Dragons: Rhaenyra Overthrown" chapter in Fire & Blood, Helaena died shortly after Rhaenyra Targaryen's conquest of King's Landing. The historical accounts agree that she died after throwing herself from a window in Maegor’s Holdfast, landing impaled on iron spikes in the dry moat below. The exact cause of her death is subject to speculation among in-universe historians.
Grand Maester Munkun suggests Helaena took her own life after witnessing the executions of Ser Thoron and Ser Denys, who had attempted to free Corlys Velaryon. Septon Eustace offers an alternative account, stating that Mysaria, Rhaenyra’s mistress of whispers, informed Helaena of her son Maelor's death – having been killed by a mob – leading Helaena to die from grief. A darker rumor circulating within King's Landing, also noted in Fire & Blood, posits that Rhaenyra herself ordered Helaena's death as a means of prolonging her suffering before Prince Daeron could reclaim the city. Regardless of the precise reason, Helaena's death prompted riots among the commoners of King's Landing.
As of the current point in the House of the Dragon series, Helaena Targaryen is still alive. However, with Rhaenyra's capture of King's Landing and the subsequent imprisonment of Helaena and her mother, Alicent Hightower, her death in captivity appears imminent. The series has demonstrated a willingness to deviate from the source material, as seen with the altered fate of Laenor Velaryon, whose death was faked to allow him to escape. While not confirmed, it remains a possibility that Helaena's demise could also be presented differently on screen. The absence of her youngest son, Maelor, in the television adaptation removes the impetus for her grief-stricken suicide as described in the book, leaving her fate open to interpretation within the show's narrative.
Rhaenyra has previously shown a degree of fondness for both Helaena and Alicent. Nevertheless, the political climate within Rhaenyra's Black Council may not afford them the same leniency. The circumstances surrounding Helaena's eventual death, whether it mirrors the book or is altered for the series, will become clearer as season 3 unfolds.