In the 24th century, the Human Empire is still recovering from the brutal Vague War, a conflict that, at various points, involved fighting all known alien races. A new technology called aTan allows humans (with enough money to afford it) to be resurrected upon death. The aTan Corporation has since become a powerful entity within the Empire.
A professional bodyguard named Kay Altos wakes up in a hotel room on Kailis, bound and about to be killed by a teenager with a pain-inducing weapon. It turns out that, when landing his ship the day before, Kay accidentally killed the boy's sister, who had sneaked into the spaceport to sell the new arrival something. Unfortunately, Kay hadn't had time to renew his aTan, so his death would be permanent. He tries to trick the boy but ends up being killed anyway.
To his surprise, he wakes up on Terra at the private aTan facility of Curtis van Curtis, the founder and owner of the aTan Corporation, who has chosen to resurrect Kay after his official death. He offers Kay a job, to escort his twelve-year-old son Arthur to a backwater planet called Grail. After some reservations, Kay accepts. Van Curtis promises him an eternity of free aTans if he succeeds and an eternity of torment if he fails. He has Kay train for several days under a Bulrathi instructor, whom Kay ends up killing after the training is over for participating in the destruction of his home planet. Kay and Arthur are given new identities as a father-and-son crew of a trading ship, flying from Endoria to Kailis. Van Curtis recreates an accident aboard a "ship" in an imitation chamber that result in their deaths. Fortunately, the "Ovalds" have aTan and are resurrected on the planet Incedios. As they leave the local aTan facility, they find out that the planet is in the middle of a civil war with the use of biological weapons. They embark on a trek to reach the spaceport on the other side of the local capital city, which is under siege by rebels. They manage to "borrow" a farming vehicle at a nearby farm and reach the spaceport, just in time, since Kay has been infected by a Synthetic Plague. He is healed at the Imperial spaceport, while a local Imperial Security Service official named Isabella Kal verifies their story. After Kay is healthy again, he and Arthur book passage aboard a cruise liner heading for Epsilon Volantis. Meanwhile, Isabella's Number Two Louis Nomachi manages to figure out Arthur's true identity. He informs his boss, but it's too late, the "Ovalds" are already off the planet. The two of them decide to intercept the heir to the aTan Corporation at their destination to torture the kid for the secret to immortality.
Aboard the cruise liner, Arthur reveals to Kay that he has been killed over seventy times already and doesn't want to die again. A few days into their flight, Arthur finds out that the cruise liner is dropping off a shuttle to Dogar. While it's not exactly safe, Kay manages to book passage aboard the shuttle for the two of them, rightly expecting ISS to be waiting for them at Epsilon Volantis. After dropping out of hyperspace, the shuttle is stopped by a quarantine vessel and is boarded. The crew of the quarantine vessel exchanges several words that Kay recognizes as in the language of the Darlok, a race known for being able to recruit spies almost everywhere. He starts shooting in the shuttle, but everyone is stunned by a shock grenade. The shuttle passengers are taken aboard the quarantine vessel and then to an unknown destination.
Meanwhile, Kal's ISS ship intercepts the cruise liner at Volantis. She finds out about the unscheduled shuttle drop and uncovers a Darlok conspiracy, which also involves the cruise liner's captain, who has been regularly dropping off passengers at Dogar to be picked up by Darlok agents, who are then brainwashed into becoming loyal Darlok spies.
The shuttle passengers are taken to Layon, a Darlok colony, where they are taken to a special prison to await "processing". Kay asks to speak with a Darlok spy he once met, who has also taught him the Darlok language. Kay meets him and is surprised to see a Darlok, not a brainwashed human. The Darlok explains that he's the same individual Kay met, forcing Kay to realize that the Darlok don't brainwash their captives, they overwrite their personalities with Darlok ones, so he and Arthur are going to die anyway instead of becoming loyal Darlok agents. While in captivity, he also encounters a doctor from Incedios named Vyacheslav, who seems awfully chipper about being in Darlok hands. Kay asks his old friend to keep him awake during the procedure. When Kay, Arthur, Vyacheslav, and a girl are taken to a chamber, where the girl is implanted with a small green snake. Kay realizes that the snake is a true Darlok, a parasite organism. The tentacled humanoid bodies they are frequently seen as are merely their standard hosts. He attacks the guards and, along with Arthur and Vyacheslav, manages to defeat them. Vyacheslav reveals himself to be an Imperial special forces operative, who has been sent to find out the true nature of the Darlok race. He kills himself in order to get back to his HQ using aTan, while Kay and Arthur try to get out on foot. Kay realizes that the planet is being bombarded by someone. He initially assumes it's the Empire, but it turns out to be the Silicoids, a race of floating silicon columns, the only race immune to being taken as hosts by the Darlok. They have come to Layon specifically looking for Arthur van Curtis. Kay and Arthur agree to leave with them.
Meanwhile, Isabella Kal convinces an Imperial Forces admiral named Lemak, a war hero, to give her a small squadron to track the Darlok ship that has taken the shuttle. They arrive to Layon just in time to watch the entire Silicoid fleet lay waste to the planet and depart. She orders the squadron to shadow the fleet.
Aboard the Silicoid ship, Kay and Arthur meet Sedimin, the Foot of the Silicoid Foundation (or Basis), the ruler of the Silicoid race. Sedimin explains that they are worried about Arthur's continued attempts to get to Grail and fear that he might obtain another aTan-like technology that will destabilize the galaxy's balance of power. They have previously prevented Arthur's attempts either directly or through agents. At their quarters, Arthur explains to Kay that he's not Curtis van Curtis's son, he's his clone. By Imperial law, clones have no rights, so Arthur is legally listed as van Curtis's son and heir. Kay admits that his original name is Kay Dutch, he is a genetically-engineered super and is likewise illegal by Imperial law. Arthur then has a one-to-one audience with Sedimin and reveals to him the true nature of what he's looking for on Grail. Sedimin chooses to let them continue on their way by dropping them off in a tiny express pod. They end up landing on the planet Tauri, which is normally a paradise given to Vague War veterans and their descendants. However, they accidentally crash-land in a sump, an area of perpetual winter. Kay manages to carry Arthur to civilization, where they are taken in by an old woman named Henrietta Fiscalocci.
Kal's squadron manages to detect the express pod, and she goes to Tauri. Her people track down Arthur and manage to take him, while Kay is away. She leaves two of her people behind, a man named Kadar and a Bulrathi named Ahar. When Kay returns, he finds out about the assault and confronts Ahar. He uses the knowledge gained from van Curtis's Bulrathi instructor to kill Ahar in unarmed combat, while Henrietta kills Kadar with a single-shot blaster. Kay quickly realizes that "Henrietta" is really Wanda Kahowski, a retired terror group commander, one of the deadliest women in human history. She provides Kay the details on Kal and her people and gives him a weapon with which to take on the Imperial marines working for Kal.
Needing his own ship back, Kay travels to Kailis. While there, he discovers the identity of the boy who killed him and abducts him on the way home from school. The boy, Tommy Arano, turns out to be Arthur's aTan clone with his memories wiped. He reveals to Tommy the truth about his origins and asks him to come with him. After a while, Tommy agrees. Realizing he needs help, Kay travels to Gorra to see an old friend, a fellow super named Lyka Seiker, who is currently the Mother of the Family, the largest criminal syndicate in the galaxy. Lyka uses her contacts to track Arthur down to a heavily-defended Imperial Forces orbital base. Kay asks her for weapons, armor, and soldiers to help with rescuing Arthur. She agrees despite the risk to her own position and life. Kay's ship is disguised as a supply vessel, and Kay is given an android, a Meklar, and two brainwashed thugs as help, not to mention top-of-the-line weapons and Power Armor for both Kay and Tommy.
They manage to infiltrate the Imperial base and get to Arthur, who has been tortured all this time without so much as a peep. Unfortunately, his body is slowly dying, and there's nothing to be done about it. Kay manages to get both boys out of the base, while losing the two thugs and the Meklar (the latter survives but is captured). They head to Ursa, the Bulrathi homeworld, in order to get supplies and prepare for their final jump to Grail. When they finally get to Grail, they find Lemak's Imperial destroyer waiting for them. Kay's ship's AI slams the ship into the destroyer's shields, causing Kay and the boys to be resurrected down on the planet. Kal demands to be taken to the planet, but Lemak explains that he has just been recalled. The Human Empire is at war with the Darlok Unity. Kal has herself shot in order to follow Kay via aTan.
Kay, Arthur, and Tommy rent an off-road vehicle and go into an area known locally as the Dead Zone, since machines seem to always malfunction in it. Kal obtains a flyer and follows them. She catches up to them and tries to kill Arthur. However, the beam does no damage to the boy, since he appears to be protected in the Zone. Having gone mad, she walks into a river and allows herself to drown (she is later resurrected and put into a mental institution). Arthur reveals the nature of his trip to Kay. Apparently, during the Vague War, Curtis van Curtis found the planet Grail and landed on it. There, in the Dead Zone, he found God, which he perceived as a machine. Being the first to find him, God offered van Curtis a universe for himself, just like this universe was created for someone else. Fearful, van Curtis asked to wait, so the God machine gave him the plans to the aTan device, which would allow van Curtis to think for as long as he wanted. Now, van Curtis wants to get the plans to a new piece of technology known as the Line of Delirium (or Dreams). He plans to sell personal universes to humanity. Realizing that this will destroy the Empire, Kay tries to kill Curtis van Curtis, who appears near them, but the Zone protects him as well. Van Curtis and his clones then walk across a lake, but Tommy chooses to go back and leave with Kay. Kay is disappointed that Arthur didn't follow suit. Van Curtis and Arthur vanish in the middle of the lake, while Kay and Tommy leave the planet.
Four years have passed. Kay and Tommy (who now calls himself Tommy Curtis) chase down an Alkari ship, and Kay asks the ship's commander Truthseeker to meet him for a brief audience on a neutral planet, which happens to be the site of a devastating battle between the Human Empire and the Alkari Branch decades prior. While there, the Alkari reveals that he knows that Kay participated in the slaughter of colonists on Haaran, who were trying to defect to the Alkari, earning himself the nickname Measles. The Alkari reveals that his people have been able to scientifically prove the existence of God and the deterministic nature of the universe. Thus, they are working on a way to shift their entire area of space into the metaspace between the universes, so a new universe if created just for them. Kay, still concerned with Curtis van Curtis ruining the Empire to spite the Emperor, whom Curtis believes is the one, for whom this universe was created, decides to stop him no matter what. This can only be done one of two ways: kill van Curtis or kill the Emperor. The problem is that both are, effectively, immortal. However, the Emperor is marginally less protected than Curtis.
They travel to Tauri, where Kay recruits Henrietta Fiscalocci (AKA Wanda Kahowski) and Rachelle Haney to their task, as the Emperor is scheduled to visit Tauri during a ritual known as the Prostration. Henrietta convinces Rachelle to allow them to use her little sister as an agent of influence, who will be programmed to drive the Emperor slowly insane. Kay suggests using the knowledge that Gray is the creator of this universe as the trigger phrase.
In the meantime, Gray sends Commander Vyacheslav Shegal, his top operative, to investigate the aTan Corporation's latest project. He infiltrates an aTan facility as a technician and manages to discover what the Line of Dreams is all about before committing suicide and reporting back to the Emperor.
When the Emperor arrives to Tauri, Rachelle's sister greets his shuttle and charms him. She becomes the Emperor's temporary girlfriend. The courtiers start noticing Gray becoming more unhinged as time goes on. However, Kay eventually realizes that he was wrong about Gray being the creator of the universe. Thus, the trigger phrase fails to destroy Gray's mind and only results in him becoming aware of the attempt on his sanity. An Empire-wide manhunt is declared on Kay and Tommy, and they barely manage to flee Tauri. Rachelle is arrested, but her status as a minor keeps her safe from torture. Henrietta/Wanda opts to commit suicide rather than be captured, having cancelled her aTan beforehand. Arthur van Curtis offers his services to the Emperor to help chase down Kay and is forced to work alongside his former captor Admiral Lemak.
At a press conference, Curtis van Curtis announces the existence of the Line of Dreams and offers it to the Empire at dirt-cheap prices, touting it as a place to realize one's dreams. The Emperor tries to figure out how to stop van Curtis from destroying the Empire with this new development. He sends Shegal to meet with Arthur aboard Lemak's flagship and try to convince him to take his father's place as the master of aTan.
Kay and Tommy flee to Gorra, where Kay contacts Lyka and asks for her help. She picks him up in her ship, a converted destroyer, her people disposing of his own, and gives Kay and Tommy a tiny ship, which they plan to use to reach Grail and meet God. Kay chooses Fieras, the Mrrshan homeworld, as a refueling point in order to visit an old friend and also believing that Lemak would never go there due to an old score between him and the Mrrshans. On Fieras, Kay and Tommy pretend to be traveling salesmen, awaiting for their ship to be refueled. However, a savvy Mrrshan passport control officer quickly figures out who they are and enlists the help of a coworker in order to capture them and get the glory. Kay and Tommy head out of the spaceport and into a nearby town, where Kay finds the home of an old Mrrshan named Jassan, who had been one of his teachers during his time in a traveling circus. They reminisce about the old times and speak about God, despite Mrrshans being atheists, then Kay and Tommy head back to the spaceport. The two Mrrshan officers make a move, which ends with Kay starting a shootout at the busy spaceport. Kay and Tommy barely manage to make it back to their craft and take off.
In the meantime, Arthur has figured out where Kay would go and convinces Lemak to take his fleet to Fieras. Lemak's destroyer intercepts Kay and Tommy's ship and captures it. Vyacheslav Shegal arrives in a fast courier ship and demands to be the first to speak with the prisoners. During the conversation, Kay realizes that Shegal, not Gray, is the one, who created this world. As a special operative of the Emperor, he is free to live the life of adventure, never to grow bored. Shegal decides that Kay and Tommy must not make it back to meet the Emperor, as they know too much.
Arthur disables his bodyguard Marjan, puts on Powered Armor, and hijacks the destroyer's bridge, threatening to drop the ship out of hyperspace at full speed, which will result in extreme Time Dilation. Centuries would pass outside by the time the ship's speed is brought down to normal. Lemak agrees to send Kay and Tommy (also in armor) to the bridge. Marjan and Shegal separately head to the bridge to resolve the hostage situation before it's too late. Marjan arrives first and mortally wounds Arthur, before Kay kills her. The fight interrupts the attempt to decelerate the ship, dooming the destroyer and her crew to a one-way trip into the future. In the moments before the ship exits hyperspace, Kay and Tommy launch themselves out the airlock, hoping to be thrown out into real space once they leave the hyperfield. Shegal does the same. Lemak orders crewmembers with aTan to kill themselves and report back to HQ, himself staying behind. As Lemak's ship is passing into the future, Kay and Tommy are rescued by a merchant, who picks up their distress call, and whose ship makes the jump to their location instantaneously - an unheard of event. The merchant delivers them to Grail.
Arriving on Gorra, the weary Emperor Gray decides to write a new will, summoning Curtis van Curtis (whom he pardons for trying to destroy the Empire), the Patriarch of the Church of the Unified Will, and Lyka Seiker as three of the most powerful individuals in the Empire, besides himself. They bear witness to his new will and swear to ensure that it's upheld. Gray then summons a lieutenant from his personal guard and asks him to sneak him out of his residence. Gray then goes to an aTan facility and trades his aTan for a Line of Dreams. The technician realizes who he's dealing with only after the process has begun and can't stop the Emperor from leaving this universe.
On Grail, Kay and Tommy meet Arthur, who arrived via aTan. Kay takes Arthur to see Isabella Kal at a mental hospital to show him that the past is harmless. They rent a jeep and head to the Evil Lands. Meanwhile, Shegal arrives to Grail's orbit and orders troops to surround the Evil Lands but not to cross their edge. His own landing pod arrives next to the Threshold, and he waits for Kay and the boys to arrive. After they meet, both try shooting one another, only to find out that the Threshold is protecting them from death, so they try fighting hand-to-hand, with Kay losing to the much more experienced operative. Shegal cuffs Kay and prepares to drag him out of the Evil Lands and kill him as a nuisance, and to take one of the boys as van Curtis's replacement. But then he's notified of the Emperor's disappearance and will, wherein all the conspirators are pardoned. Shegal is forced to leave alone. Kay decides to enter the Threshold and ask God a question. While he's gone, Tommy says goodbye to Arthur and announces his intention to go through the Line of Dreams, seeing himself as little more than an extra and admitting that he wants a life of adventure. He steps through the Threshold.
Kay finds himself on a cliff overlooking an ocean and a cloudless sky. Everything is quiet, and there's not a single trace of life. He talks into thin air for a little bit, realizing that there can be no God for someone who doesn't believe in anything and who has no dreams for the future, no illusions. He turns around and leaves with a renewed sense of purpose.
The events take place on a small human colony far from Terra. It's a quiet, pastoral world with a race of primitive natives called the Abori, whose bodies produce pearls that are highly valued on the civilized worlds. The protagonist Alexey Kononov dreams of someday leaving the planet but is forced to come to the realization that he'll probably end up marrying his old schoolteacher, since everyone else has already paired up.
An interstellar regatta unexpectedly makes a stop on their planet. The lead yacht's crew, a ten-year-old girl named Anne and her brother Artem, explain that their father accidentally discharged his blaster and died. They're not worried, as he had aTan, but now they need a third person to continue the race. Alexey considers joining them, but realizes it's too dangerous, since the girl is a trained killer.
Just then an Imperial courier ship arrives and informs the colonists that a Vague War-era Psilon assault cruiser has entered the system, having spent the nearly two centuries since the war traveling at near-light speeds. The Psilon crew is still following their original orders to capture the planet and wipe out the inhabitants. Should the Psilons succeed in establishing a foothold, the Imperial fleet that's currently on the way will simply turn the entire planet to slag rather than risk a frontal assault. The local garrison mobilizes all able-bodied colonists into a militia and forbids anyone from leaving the planet under the penalty of treason. The children and the elderly are taken to the woods, except for Anne and Artem, since they are technically adults according to their planet's laws.
The militia is issued weapons and camo gear and is told to set up near the three firing positions around the spaceport. The bunkers will attempt to shoot down the Psilon assault shuttles, knowing full well that the escorting fighter craft will destroy the bunkers in turn. However, to everyone's shock, the Psilons wipe out the bunkers well before they can fire, leaving the assault shuttles free to land and disgorge their Psilon marines in advanced power armor. Alexey's group attempts to resist and even inflicts a small number of casualties, but the Psilons are far too advanced and powerful, so they are forced to flee. He suddenly recalls that there's a fourth bunker that everyone seems to have forgotten about. He, Anne, and Artem head there and enter the bunker. To Alexey's surprise, the bunker's systems are active. He is recognized as the commander and learns that the Psilon cruiser is on a landing approach. Attempting to shoot it out of the air will probably be unsuccessful, so he orders the bunker to open fire on the Psilon marines that are in the process of mopping up his fellow colonists. When Anne tries to interfere, he has the bunker place a force field around him and tells her that he knows that she informed the Psilons about the other three bunkers in exchange for free passage out of the system. The unexpected attack deals significant damage to the landing force, but the Psilons eventually damage the bunker beyond repair, so Alexey, Anne, and Artem come out to the surface.
Alexey encounters a Psilon out of his armor and considers shooting him, only to lower his weapon. He turns around to find six Psilon marines facing him. One of them tells him that he has shown sufficient combat valor to merit imprisonment instead of extermination. Then an Abori walks up to them and offers to trade a pearl for water. The Psilons exterminate the native without a second thought. While the Psilons are watching their cruiser come in for a landing, Alexey notices an entire swarm of Abori appear from the woods and move to surround the invaders. The Psilon marines start shooting, but the Abori use their ability to emit directed microwave beams to fry them. Then they turn their ability on the cruiser and slice it in half as it's landing. They then proceed to swarm the spaceport to finish off any of the remaining Psilons, as well as Anne, whom they also perceive as a threat. As they're leaving, one of them turns to Alexey and warns him not to be as "naughty" as the Psilons, which is the first time an Abori has ever spoken instead of merely parroting human words. While Artem hasn't ordered Anne to deal with the Psilons, he knew about it. Instead of waiting for Alexey to tell the authorities, he asks Alexey to allow him to leave on his own terms, presumably through aTan. Alexey obliges.
In the aftermath, Alexey is sitting alongside his friend among the soldiers and waiting for the arrival of Imperial ships to help the survivors. They speak about his friend leaving and eventually forgetting this planet, just like Alexey will move on and forget him.
