This post contains spoilers for the “Dune” saga.

In Denis Villeneuve’s “Dune: Part Two,” Lady Jessica (Rebecca Ferguson) telepathically communicates with her fetus, Alia, who, along with her, is transformed after being exposed to the Water of Life. As a fetus, Alia is strangely in tune with Jessica’s plans regarding her son, Paul (Timothée Chalamet), as she actively urges her mother towards a distinct path. In one of Paul’s many visions, we get a glimpse of a grown-up Alia (Anya Taylor-Joy), whose presence is set up to be monumental in the tense, bloodstained chapters to come. Notably, though, the same character is fleshed out differently in David Lynch’s “Dune.” There, Alia (Alicia Witt) is a book-accurate superpowered toddler who yeets Baron Harkonnen (Kenneth McMillan) across Arrakis with the sheer power of her mind.

While Villeneuve has been closely following Frank Herbert’s “Dune” book series for the most part, he makes the choice to omit toddler Alia from “Part Two” for creative reasons. After all, the idea of a toddler with the mannerisms and acumen of a grown adult is challenging to pull off on a technical level and runs the risk of coming off as unintentionally silly. Of course, this omission also points to an inevitable time jump, with Alia’s arc being condensed and limited to her adult self.

In Herbert’s “Dune,” toddler Alia is indispensable to the tale, as her journey runs parallel to Paul’s, creating a mirroring effect that is both alarming and tragic. This is made especially clear in Herbert’s novels “Dune Messiah” and “Children of Dune,” which position the grown-up Alia as a messiah figure of another kind, doomed to repeat the mistakes of the past. The complex allure of Paul often overshadows the crucial role his sister plays, but Alia dons many faces throughout her tragically short life: a perceived Abomination, a Revered Mother, a demi-goddess, and a destructive force of nature. With this in mind, let’s trace her journey, starting when she is a preborn with astounding cognitive abilities.

Eight months after Duke Leto I’s death, Alia is born, armed with the consciousness of an adult Bene Gesserit and the terrifying ancestral memories that come with it. The Fremen are immediately wary of her, and the Bene Gesserit deem her an Abomination, a derogatory term used for those unable to control genetic ego-memories. As Alia has access to vast vistas of knowledge across space and time, she is feared, as the Bene Gesserit believe that her fractured psyche will inevitably shatter at some point (more on this later). Unlike Paul and Jessica, whose eyes naturally turned blue due to prolonged exposure to spice melange on Arrakis, Alia was born with them. A combination of these factors paints Alia as a near-mythical figure, both worshipped and feared by those prone to religious indoctrination and superstition.

Paul’s status as a messiah among the Fremen shapes Alia’s upbringing, leading to her direct involvement in the Desert War. This is not surprising, as her advanced abilities allow her to lead attack groups and decimate enemy squads until she is captured in a Sardaukar raid. Fret not, she escapes during the Battle of Arakeen and makes sure to prick Baron Harkonnen (who is revealed to be her grandfather in that moment) with a poisoned gom jabbar. Her vicious fearlessness in battle is important to note here, as it eventually earns her the holy epithet “St. Alia of the Knife.” Why? Well, during the war, she goes around stabbing fallen enemy soldiers with her chrysknife to extract the water stored in their bodies.

As you might have gauged, Alia is someone who quite literally contains multitudes, as she holds ancestral memories and dons many masks. Herbert described Alia’s complexity like so: “She is vulgar, witty, knowledgeable to a depth that terrifies, cruel when she is most kind, unthinking while she thinks, and when she seeks to build she is as destructive as a coriolis storm.” These words reveal their true meaning in the books that follow “Dune,” so let’s take a closer look at Alia’s journey in these volumes.

Characters in “Dune” have a way of coming back long after they’re dead, and Duncan Idaho is no different. When Duncan returns as the ghola Hayt, his intentions and motivations are completely different, as he is secretly meant to serve as a trap for Paul, who is now Emperor. Alia, a grown adult now, develops a charged relationship with Hayt, and most of her inner workings in “Dune Messiah” are revealed through this complicated relationship. After Hayt is exposed as a traitor, the memories of the actual Duncan Idaho are eventually restored, which also reinstates his loyalty to House Atreides. When Paul goes blind and chooses self-exile, Alia is named Regent in his absence, and she takes on the mantle after marrying Hyat.

This is where things take a dark turn. Alia, whose mind is always overpowered by strong ancestral personalities, is unable to cultivate a core personality strong enough to resist influence or complete possession. A psychic split starts forming, with Alia overindulging in spice to push her powers to their limits, moving her closer to becoming an Abomination due to her intense and reckless impulses. By the time we reach “Children of Dune,” Alia has transformed into an extremist; she manipulates people using fear in the name of faith and religion, increasingly giving into the more ruthless parts of her personality. Along the way, her efforts to bolster her political standing and religious mystique turn violent, and she adopts a tyrannical approach to her interim rule as Regent. Her escalating paranoia and power-hungry nature gradually lead to her being possessed by Baron Harkonnen, who takes advantage of her lack of a strong core personality and pushes her to become all the more murderous.

Paul’s subsequent return from exile serves as a tragic turning point in both his and Alia’s stories. Once Paul exposes his sister’s status as an Abomination to the Fremen, the zealous priests murder him, leaving a grieving Alia to desperately fight off the endless personalities trying to seize control of her mind and body. Jessica not only witnesses these events but is also ultimately helpless to stop her daughter when, upon briefly regaining command of her physical being, Alia leaps out of an open window to her death.

In the end, Alia dies as both a tyrant and a martyr. Her final act may save countless lives, but it dooms House Atreides.