“Castle in the Sky(Studio Ghibli Official)” is an animated theatrical work directed by Hayao Miyazaki, released in 1986.
This time, I want to explore a mystery that wasn’t explained in the main story of “Castle in the Sky”: “Why did the robot trooper fall from Laputa?” It’s depicted so naturally in the flow of the story that it’s easy to overlook, but it’s still unclear why it fell.
At the very least, the moss-covered robot that Pazu and Sheeta encountered was functioning normally, as were the combat robots that appeared at the end of the film. So why did that one particular robot fall? This time, I’m going to share my personal thoughts on this matter, though they may not be very convincing.
Furthermore, I will also consider the narrative significance of the fact that “a robot falls from the sky.”
*This article is an English translation of the original Japanese article, “「天空の城ラピュタ」で何故ロボット兵は空から落ちてきたのか?“.
Let an AI walk you through the highlights of this post in a simple, conversational style.
- The fallen robot trooper was a guardian of Laputa’s seal.
The robot that fell to the ground had ceased to function due to energy depletion, but its role was to protect Laputa’s seal. It is thought that it failed in its attempt to intercept Pazu’s father, who was the first to approach that seal. - For Pazu, Sheeta was a “spider’s thread.”
Sheeta, who fell from the sky, was a “symbol of hope” for Pazu, who wanted to believe in his father. She was like a spider’s thread of hope extended to him in his despair. With her appearance, his daily life began to shine again. - For Muska, the robot’s fall was “proof of history.”
The Muska clan continued to believe in the bloodline and history of Laputa but were not believed by the world. The robot’s crash became the “tangible evidence” that justified their history and pride, spurring on Muska’s long-held ambition.
The Reason the Robot Trooper Fell.

Energy Depletion
The most crucial scene for thinking about this problem is likely when the robot receives energy from Sheeta’s Aetherium stone. This implies that the robot’s energy was depleted at that point. Therefore, it’s natural to assume that the robot stopped moving not because of the impact of the fall, but because it had already run out of power.
While that seems natural, the real question is what state that robot was in back on Laputa. What was it doing while it was losing energy?
Its Role in the Sealed Laputa
The first robot Pazu and Sheeta meet on Laputa was surely a gardener robot, not a combat one. It had been endlessly performing basic maintenance on the abandoned Laputa. Come to think of it, the other gardener robots had also stopped moving, which means the robot that fell to Earth wasn’t the only one with depleted energy. One can only wonder how long they had been active on the deserted Laputa. Just imagining it is poignant.
But while it’s sad, I can imagine the role of the gardener robots. What’s harder to grasp is the role of the robot that fell. The other combat robots were properly stored away, which means that one unit was not.
From here on, this is baseless speculation, but I believe the meaning of the combat robots changed before and after Laputa was sealed. Before the sealing, their purpose was offense and defense. After, their mission would have been to protect that very seal.
However, it wouldn’t be strange to think that a single robot was sufficient to guard the seal of Laputa, the mightiest city in the sky. In fact, the robot that fell was “invincible” on the ground. Therefore, a single unit would have been more than enough to eliminate anyone trying to break the seal (and besides, the “adverse wind” was already hiding Laputa within a thunderhead).
In other words, that robot would only activate when someone appeared who could break the seal.
I think you all see where this is going. The first person in “Castle in the Sky” to break that seal was “Pazu’s father.” This means that on the day Pazu’s father approached Laputa, that robot tried to launch an attack, but being already out of energy, it was unable to pursue him and simply crashed to the ground. To put it another way, Pazu’s father had a very close call.
So, what do you think? I know it’s not the most convincing theory, but I don’t think it’s too bad. Don’t you think I’m on to something?
The Significance of the Robot Trooper’s Fall.

The Meaning of Sheeta’s Fall – Pazu’s Spider’s Thread
From here, I want to shift from the question “Why did the robot fall from the world of Laputa?” to “What is the narrative significance of the robot’s fall?”
The most important and simple comparison is Sheeta. Sheeta’s fall has quite a profound meaning within the context of Laputa. To understand it, we must reflect on Pazu’s daily life.
Because Pazu’s father discovered Laputa, he was branded a liar and died in disgrace. Pazu, who “wanted to believe” in his father, spent his nights building an airplane while enduring harsh labor.
As many of you have likely realized, there’s no way a plane built by a child alone could ever reach Laputa. Pazu could not have cleared his father’s name on his own.
Moreover, as time passed since he first heard the stories of Laputa from his father, Pazu himself must have had slight doubts about his father’s words. Still, he wanted to believe, so he built the plane. It wasn’t that he believed, but that he *wanted* to believe.
For a Pazu in such a state, the appearance of the girl, Sheeta, falling from the sky must have been like a spider’s thread of hope. A single, thin thread leading to the very thing he wanted to believe in. That was surely Sheeta. And with her appearance, Pazu’s days of despair truly began to shine. He says as much to Sheeta in the film, but for Pazu, it must have been a greater blessing than we can grasp from his words alone.
So, what does it mean for “the robot to fall”? Let’s take a slight detour to consider this.
The Aspiration of Muska’s Clan
Let’s first reflect on Muska’s life.
In the film, Muska appears to be a competent man, leading the search for Laputa and maneuvering quite skillfully. However, as he himself told Sheeta, if the robot hadn’t fallen, “no one would have believed in Laputa’s existence.”
So, what was Muska’s life like before the robot fell? It was likely the same as Pazu’s father’s, who died in disgrace.
Like Pazu, Muska believed in Laputa, and even more so, he believed in his royal lineage. It’s hard to imagine his life was smooth sailing. If Muska, or his clan, had been doing well in the world, he would not have sought Laputa. If that were the case, he would have lived peacefully as a member of such a lineage and satisfied his pride. However, given the intense pride radiating from the Muska in the film, such a situation is unimaginable.
Perhaps the Aetherium stone and spells that Sheeta’s clan never abandoned were, for Muska’s clan, the history of Laputa itself.
Sheeta’s clan held onto the stone and spells without understanding their meaning. Muska’s clan, without the power, held onto the history. It’s likely that by dividing the royal family in this way, they sealed away the existence of Laputa, much like a “nuclear weapon” in the modern world.
However, Muska’s clan, unable to part with their history, could not cast away their “pride.” It was likely Muska’s ancestors who opposed abandoning Laputa until the very end. But, correctly understanding the limitations of Laputa’s way of life, I believe they chose history and gave up the Aetherium stone (believing it could be recovered).
But even if this history was passed down through Muska’s clan, it’s a story no one else would believe. When Muska reached Laputa, he opened his notebook and read the Laputian script, but to an ordinary person, it would all seem like a “wild tale.”
But then, a robot fell from the sky.
The crash of that robot fully affirmed the long-held wish of Muska’s clan, who had never lost their history. It must have been the same situation for him as it was for Pazu, who grasped the spider’s thread named Sheeta amidst his days of harsh labor.
I may have let my imagination run a bit wild talking about his clan, and perhaps didn’t convey Muska’s own harsh life well enough, but he desired the revival of Laputa from the bottom of his heart, and he lived a life harsh enough to make him wish for it.
For Muska, the “falling robot” is what the “girl falling from the sky” was for Pazu.
I know this was a rather speculative piece, but I don’t think it’s too outlandish.
The images used in this article are from “Studio Ghibli Still Images“.
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