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Exodus: The Helium Sea

Read by John Lee
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On sale Jun 16, 2026 | 23 Hours and 56 Minutes | 9780593912959

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The epic conclusion of the Archimedes Engine duology by legendary author Peter F. Hamilton. Set in the universe of EXODUS, a new sci-fi action-adventure RPG coming soon from Archetype Entertainment.

For millennia, the Crown Dominion has been at relative peace, with the Celestials in control and the human population little better than serfs. But now the Crown Dominion is facing a crisis of epic proportions—one that could change the balance of power in the Centauri Cluster forever—as an exiled faction that has been waiting for seven thousand years beyond the Helium Sea has returned to claim their vengeance.

For Finn and his human allies, who have ended up at the center of this conflict either through circumstance or manipulation, this is an unprecedented opportunity. If they can band together, they may be able to outwit the Celestials and finally earn their fellow humans a place of independence and power in the Crown Dominion. But first they must locate and master ancient artifacts of immense power that could give them a needed edge in the conflict ahead. And all while ducking the forces that are determined to knock them off the board for good.
Chapter One

It had taken Chief Octain and his small team of engineers a frantic thirty minutes to load a worn-­out remote maintenance pod with modules from other ancillary craft. Even as the old pod was ejected from the Diligent’s hangar they were still running diagnostics, praying the kludge would work—­at least for a while.

It drifted away from the kilometer-­long starship, cold gas thrusters burping to stabilize its slow tumble. Sensors started to scan around. On one side of the pod was a broad circle of darkness where the lonely Gate of Heaven blotted out the shimmering multicolored clouds of the Poseidon Nebula, which surrounded the Kelowan system. The Diligent’s green-­and-­orange navigation strobes were visible against it as the ancient starship glided in toward the center of the colossal Elohim machine.

On the opposite side, where Kelowan’s star gleamed warmly, the pod’s onboard network identified the thirteen bright lightpoints of the habitable planets. Hexagonal panes, jutting out from the pod’s fuselage like a set of dark asymmetric sails, changed their array phasing to focus on those distant gleams of life. There was also an omnidirectional broadcast, boosted by additional power cells, that the technicians hoped would last long enough as they handled voltage levels far beyond their intended limits.

The transmission began. Like the pod itself, it was a hastily contrived message that the human societies of the Kelowan system would come to call The Sibling Plea.

Finbar Jalgori-­Tobu sat on a chair in the Diligent’s command and control center, looking worn to the point of illness as he stared unflinchingly into the camera. He was flanked by his sisters. One, Otylia, was his twin—­now separated by forty years biological aging from the cost of time dilation, but their similarity still obvious nonetheless. The other was his elder sister, Zelinda, the ex-marchioness of Santa Rosa, whose reign has lasted less than an hour after her mother had been killed.

That death was the culmination of events whose firestorm of memories were plaguing Finn’s mind at a debilitating level. Ever since he’d bought the Diligent in exchange for Hafnir—­a broad tract of coastal land he owned, so the passengers could settle there—­he’d had one objective. He was going to be a Traveler: one of the humans who had their own starships, unearthing technological Celestial treasure from Remnant Era worlds, and bringing it home to help humans live with dignity in star systems whose Celestial overlords were implacably hostile—­when they could actually be bothered to even acknowledge humans.

Owning the Diligent had given him a unique opportunity to strike a blow for human freedom. His erstwhile friend, and fellow Traveler, Gyvoy Enfoe, had provided them with a chance to strike a real blow for the humans of the Kelowan system.

Millennia ago, Celestials had started moving Dolod, a gas giant from another star system, using one of their Archimedes Engines to fly it to Kelowan. Dolod was a strange world even by the standards of the Centauri Cluster: an iron exotic, which, if it was steered into orbit close enough to a star, would literally rain iron. The metal could be harvested from the atmosphere at a cost far lower than humans mining it from the ground on a solid world—­a change that would impoverish the human economy. Gyvoy’s plan was enticingly simple. Instead of allowing the Archimedes Engine to bring Dolod neatly into orbit, they could send it back out into interstellar space, leaving the economy of the Kelowan system unchanged. All they had to do was find a copy of the Archimedes Engine’s operating system, which would allow a uranic human to change Dolod’s course. Gyvoy, naturally, knew where to find a copy of the operating system; and Finn was a uranic human, one whose DNA had been altered so he could interface directly with Celestial technology. It was, Finn decided at the time, the wish of the Goddess Asteria Herself that had brought them all together.

Then, when the Diligent returned to the Kelowan system, he found his homeworld of Gondiar was under Celestial martial law. His parents had been killed, and his siblings were running for their lives. In his grief and outrage, he saw an opportunity to strike back against the Celestial monsters, and instead of using the Archimedes Engine to slingshot Dolod out of the Kelowan system, he used the momentum transfer to fling Boksrock—­a small lifeless world—­directly at the capital planet where hundreds of millions of Imperial Celestials lived.

Only after he’d done that did he discover that he’d been played by Gyvoy, who wasn’t even human. The so-­called Traveler was actually an Imperial Celestial agent, whose organization had their own very different agenda. Not only had Finn been completely fooled into committing what was essentially a declaration of war between humans and Celestials, Gyvoy had somehow managed to vanish, making Finn look even more guilty.

The Diligent had no choice but to flee to another star system, confirming their guilt—­although Zelinda had said they had a last chance to try and mitigate what’d happened by an appeal to the Empress of the Crown Dominion. Finn thought it a useless gesture, but by then he knew his ability to make any sort of decision had been swept away by misery and guilt, so he just agreed to everything she suggested.

“I would like to address this message directly to the empress herself,” Zelinda said with perfect composure. “Majesty, my family has been in service to you since the time humans first arrived in the Crown Dominion. We have served faithfully for all that time, and still consider ourselves loyal to you.

“Empress, we also have information that confirms that the so-­called rebellion that occurred on Gondiar, which General Avone-­Valerio now seeks to suppress, was also manufactured by a foreign dominion.

“Humans have been manipulated by an archon. He is a Celestial currently disguised as Gyvoy Enfoe, and we believe he has somehow escaped Dolod.

“In this assumed form, he’s been using some kind of neural compulsion to control various humans, including my brother Finbar. I’m sure you must realize by now that it is not possible for a human—­even uranics like us—­to alter the operation of an Archimedes Engine. We are not responsible for Boksrock’s orbit being changed, nor is this atrocity the result of some group of human malcontents attacking Kelowan. Humans benefit enormously from our allegiance to the Crown Dominion, and we do not want that to change.”

Otylia cleared her throat. “The broadcasts from my ex-­husband, Josias Aponi, are fake, cooked up by a CI routine. The Goddess alone knows, Josias is not a perfect man, but he is not stupid. More than all of us, he understands the insanity of a collapsing society, for he has witnessed it firsthand. He has walked on Old Earth, and he fled Sol because of what he saw there. That is not him in the messages agitating for further disobedience, so don’t fall for it, I implore you.”

“I was on the Archimedes Engine station,” Finn confessed at last, his eyes filling with moisture. “The archon pretending to be Gyvoy put me there. In Kingsnest, he gave me the technical knowledge of the engine’s operating system. He twisted my mind so that I had to do what he wanted—­to kill Kelowan. I don’t know which dominion he comes from, but I know he left me there and flew to another station; I don’t know which one.

“Empress, I urge you and all your forces to find him. Find out who he really is and what he wants. So many people will suffer and die until he is caught and stopped. I am so sorry for what’s happened. I wasn’t . . . It wasn’t me that did this. I would never . . .” His lips pressed together and he turned from the camera, his distress obvious. Otylia’s hand came down on his shoulder, squeezing reassuringly.

“We have nothing to gain from telling you this, Empress,” Zelinda said. “So I hope you will at least consider what we have told you.” She inclined her head respectfully. “The Jalgori-­Tobu family remain your loyal subjects.”

The message ended and began to repeat. Another kind of light illuminated the modified pod as the Diligent entered the ingress Gate—­a ring of bright radiance that flared around the machine’s rim and flowed fast down the concave surface until it was a single point at the center. The Diligent formed a small dark speck within the glare, then vanished, flung along the line of quintessence to Capo Frois by a science no human would ever understand.

Left behind, the pod continued to play the message continually for the next three and a half hours until a Celestial cargo starship arrived at the Gate. It fired a single maser cannon shot at the pod, vaporizing it. The starship sailed onward with cosmic indifference, to be embraced by the Gate and dispatched across interstellar space.
© Peter Eyre
Peter F. Hamilton is the author of numerous novels, including A Night Without Stars, The Abyss Beyond Dreams, Great North Road, The Evolutionary Void, The Temporal Void, The Dreaming Void, Judas Unchained, Pandora’s Star, Misspent Youth, Fallen Dragon, and the acclaimed epic Night’s Dawn trilogy (The Reality Dysfunction, The Neutronium Alchemist, and The Naked God). He lives with his family in England. View titles by Peter F. Hamilton
Praise for Peter Hamilton

“Counted among the greatest minds in science fiction—and one of my own favorite authors—Peter F. Hamilton has helped lay the foundations of the Exodus universe. He then expanded it with two remarkable novels: The Archimedes Engine and, most recently, The Helium Sea.”—James Ohlen, cofounder, Archetype Entertainment

“Continuing the sprawling saga begun in The Archimedes Engine, Hamilton delivers another epic tale of sci-fi exploration and adventure. The Helium Sea is a stunning, mind-expanding conclusion to Hamilton’s grand tale, and a brilliant introduction to the Exodus universe.”—Drew Karpyshyn, narrative director, Exodus

“Science fiction authors don’t get much more legendary than Peter F. Hamilton.”New Scientist

About

The epic conclusion of the Archimedes Engine duology by legendary author Peter F. Hamilton. Set in the universe of EXODUS, a new sci-fi action-adventure RPG coming soon from Archetype Entertainment.

For millennia, the Crown Dominion has been at relative peace, with the Celestials in control and the human population little better than serfs. But now the Crown Dominion is facing a crisis of epic proportions—one that could change the balance of power in the Centauri Cluster forever—as an exiled faction that has been waiting for seven thousand years beyond the Helium Sea has returned to claim their vengeance.

For Finn and his human allies, who have ended up at the center of this conflict either through circumstance or manipulation, this is an unprecedented opportunity. If they can band together, they may be able to outwit the Celestials and finally earn their fellow humans a place of independence and power in the Crown Dominion. But first they must locate and master ancient artifacts of immense power that could give them a needed edge in the conflict ahead. And all while ducking the forces that are determined to knock them off the board for good.

Excerpt

Chapter One

It had taken Chief Octain and his small team of engineers a frantic thirty minutes to load a worn-­out remote maintenance pod with modules from other ancillary craft. Even as the old pod was ejected from the Diligent’s hangar they were still running diagnostics, praying the kludge would work—­at least for a while.

It drifted away from the kilometer-­long starship, cold gas thrusters burping to stabilize its slow tumble. Sensors started to scan around. On one side of the pod was a broad circle of darkness where the lonely Gate of Heaven blotted out the shimmering multicolored clouds of the Poseidon Nebula, which surrounded the Kelowan system. The Diligent’s green-­and-­orange navigation strobes were visible against it as the ancient starship glided in toward the center of the colossal Elohim machine.

On the opposite side, where Kelowan’s star gleamed warmly, the pod’s onboard network identified the thirteen bright lightpoints of the habitable planets. Hexagonal panes, jutting out from the pod’s fuselage like a set of dark asymmetric sails, changed their array phasing to focus on those distant gleams of life. There was also an omnidirectional broadcast, boosted by additional power cells, that the technicians hoped would last long enough as they handled voltage levels far beyond their intended limits.

The transmission began. Like the pod itself, it was a hastily contrived message that the human societies of the Kelowan system would come to call The Sibling Plea.

Finbar Jalgori-­Tobu sat on a chair in the Diligent’s command and control center, looking worn to the point of illness as he stared unflinchingly into the camera. He was flanked by his sisters. One, Otylia, was his twin—­now separated by forty years biological aging from the cost of time dilation, but their similarity still obvious nonetheless. The other was his elder sister, Zelinda, the ex-marchioness of Santa Rosa, whose reign has lasted less than an hour after her mother had been killed.

That death was the culmination of events whose firestorm of memories were plaguing Finn’s mind at a debilitating level. Ever since he’d bought the Diligent in exchange for Hafnir—­a broad tract of coastal land he owned, so the passengers could settle there—­he’d had one objective. He was going to be a Traveler: one of the humans who had their own starships, unearthing technological Celestial treasure from Remnant Era worlds, and bringing it home to help humans live with dignity in star systems whose Celestial overlords were implacably hostile—­when they could actually be bothered to even acknowledge humans.

Owning the Diligent had given him a unique opportunity to strike a blow for human freedom. His erstwhile friend, and fellow Traveler, Gyvoy Enfoe, had provided them with a chance to strike a real blow for the humans of the Kelowan system.

Millennia ago, Celestials had started moving Dolod, a gas giant from another star system, using one of their Archimedes Engines to fly it to Kelowan. Dolod was a strange world even by the standards of the Centauri Cluster: an iron exotic, which, if it was steered into orbit close enough to a star, would literally rain iron. The metal could be harvested from the atmosphere at a cost far lower than humans mining it from the ground on a solid world—­a change that would impoverish the human economy. Gyvoy’s plan was enticingly simple. Instead of allowing the Archimedes Engine to bring Dolod neatly into orbit, they could send it back out into interstellar space, leaving the economy of the Kelowan system unchanged. All they had to do was find a copy of the Archimedes Engine’s operating system, which would allow a uranic human to change Dolod’s course. Gyvoy, naturally, knew where to find a copy of the operating system; and Finn was a uranic human, one whose DNA had been altered so he could interface directly with Celestial technology. It was, Finn decided at the time, the wish of the Goddess Asteria Herself that had brought them all together.

Then, when the Diligent returned to the Kelowan system, he found his homeworld of Gondiar was under Celestial martial law. His parents had been killed, and his siblings were running for their lives. In his grief and outrage, he saw an opportunity to strike back against the Celestial monsters, and instead of using the Archimedes Engine to slingshot Dolod out of the Kelowan system, he used the momentum transfer to fling Boksrock—­a small lifeless world—­directly at the capital planet where hundreds of millions of Imperial Celestials lived.

Only after he’d done that did he discover that he’d been played by Gyvoy, who wasn’t even human. The so-­called Traveler was actually an Imperial Celestial agent, whose organization had their own very different agenda. Not only had Finn been completely fooled into committing what was essentially a declaration of war between humans and Celestials, Gyvoy had somehow managed to vanish, making Finn look even more guilty.

The Diligent had no choice but to flee to another star system, confirming their guilt—­although Zelinda had said they had a last chance to try and mitigate what’d happened by an appeal to the Empress of the Crown Dominion. Finn thought it a useless gesture, but by then he knew his ability to make any sort of decision had been swept away by misery and guilt, so he just agreed to everything she suggested.

“I would like to address this message directly to the empress herself,” Zelinda said with perfect composure. “Majesty, my family has been in service to you since the time humans first arrived in the Crown Dominion. We have served faithfully for all that time, and still consider ourselves loyal to you.

“Empress, we also have information that confirms that the so-­called rebellion that occurred on Gondiar, which General Avone-­Valerio now seeks to suppress, was also manufactured by a foreign dominion.

“Humans have been manipulated by an archon. He is a Celestial currently disguised as Gyvoy Enfoe, and we believe he has somehow escaped Dolod.

“In this assumed form, he’s been using some kind of neural compulsion to control various humans, including my brother Finbar. I’m sure you must realize by now that it is not possible for a human—­even uranics like us—­to alter the operation of an Archimedes Engine. We are not responsible for Boksrock’s orbit being changed, nor is this atrocity the result of some group of human malcontents attacking Kelowan. Humans benefit enormously from our allegiance to the Crown Dominion, and we do not want that to change.”

Otylia cleared her throat. “The broadcasts from my ex-­husband, Josias Aponi, are fake, cooked up by a CI routine. The Goddess alone knows, Josias is not a perfect man, but he is not stupid. More than all of us, he understands the insanity of a collapsing society, for he has witnessed it firsthand. He has walked on Old Earth, and he fled Sol because of what he saw there. That is not him in the messages agitating for further disobedience, so don’t fall for it, I implore you.”

“I was on the Archimedes Engine station,” Finn confessed at last, his eyes filling with moisture. “The archon pretending to be Gyvoy put me there. In Kingsnest, he gave me the technical knowledge of the engine’s operating system. He twisted my mind so that I had to do what he wanted—­to kill Kelowan. I don’t know which dominion he comes from, but I know he left me there and flew to another station; I don’t know which one.

“Empress, I urge you and all your forces to find him. Find out who he really is and what he wants. So many people will suffer and die until he is caught and stopped. I am so sorry for what’s happened. I wasn’t . . . It wasn’t me that did this. I would never . . .” His lips pressed together and he turned from the camera, his distress obvious. Otylia’s hand came down on his shoulder, squeezing reassuringly.

“We have nothing to gain from telling you this, Empress,” Zelinda said. “So I hope you will at least consider what we have told you.” She inclined her head respectfully. “The Jalgori-­Tobu family remain your loyal subjects.”

The message ended and began to repeat. Another kind of light illuminated the modified pod as the Diligent entered the ingress Gate—­a ring of bright radiance that flared around the machine’s rim and flowed fast down the concave surface until it was a single point at the center. The Diligent formed a small dark speck within the glare, then vanished, flung along the line of quintessence to Capo Frois by a science no human would ever understand.

Left behind, the pod continued to play the message continually for the next three and a half hours until a Celestial cargo starship arrived at the Gate. It fired a single maser cannon shot at the pod, vaporizing it. The starship sailed onward with cosmic indifference, to be embraced by the Gate and dispatched across interstellar space.

Author

© Peter Eyre
Peter F. Hamilton is the author of numerous novels, including A Night Without Stars, The Abyss Beyond Dreams, Great North Road, The Evolutionary Void, The Temporal Void, The Dreaming Void, Judas Unchained, Pandora’s Star, Misspent Youth, Fallen Dragon, and the acclaimed epic Night’s Dawn trilogy (The Reality Dysfunction, The Neutronium Alchemist, and The Naked God). He lives with his family in England. View titles by Peter F. Hamilton

Praise

Praise for Peter Hamilton

“Counted among the greatest minds in science fiction—and one of my own favorite authors—Peter F. Hamilton has helped lay the foundations of the Exodus universe. He then expanded it with two remarkable novels: The Archimedes Engine and, most recently, The Helium Sea.”—James Ohlen, cofounder, Archetype Entertainment

“Continuing the sprawling saga begun in The Archimedes Engine, Hamilton delivers another epic tale of sci-fi exploration and adventure. The Helium Sea is a stunning, mind-expanding conclusion to Hamilton’s grand tale, and a brilliant introduction to the Exodus universe.”—Drew Karpyshyn, narrative director, Exodus

“Science fiction authors don’t get much more legendary than Peter F. Hamilton.”New Scientist

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