"The Limit" by Sergei Lukyanenko, summary Automatic translate

This book is a gripping science fiction novel, published in 2019 and 2020. The plot explores the nature of artificial intelligence and hidden aggression, where ancient supercivilizations secretly direct the evolution of younger races. Crews of exploration ships encounter a powerful and terrifying force that is methodically wiping out intelligent species across the galaxy.

Return from unreality and a new threat

The crew of the Earth corvette Twain, commanded by Valentin Gorchakov, is flying home. The ship has successfully escaped the temporal anomaly. On board are First Mate Matthias, pilot Anna Meger, physician Lev Sokolovsky, and weapons systems operator Gunther Waltz. They are assisted by young interns Alex, Teddy, and Lucia. The crew is rounded out by scientists from various races of the Cosmic Covenant. These include the British Basil, the Chinese Meili, the enormous furry Walr from the planet Hull-3, and the humanoid Two Hundred and Six – Five. Accompanying them is Ksenia, an envoy from the supercivilization Rax.

On the orbital station, Prima, another girl of the Rax race, uncovers a dark secret. A gigantic killer ship prowls space. Prima calls it "The Eraser." This enemy is causing wars on young planets. The planet Sorgos has become the latest target. Probes have detected a nuclear strike from the void there. The Rax are installing a powerful invisible weapon on an Earth corvette. Gorchakov directs the vessel to Sorgos for reconnaissance in force.

Meanwhile, Cadet Theodore notices serious glitches in Marke’s computer. For some reason, the AI is producing sequences of dates from ancient world wars. The boy secretly installs a digital worm into the system. He wants to retain manual control of the ship in case of unforeseen problems. Theodore is extremely afraid for the crew’s lives, but tells no one about the virus.

Accident at Sorgos

The starship "Friendship" is on duty in orbit around Sorgos. It was built by engineers from the Nevara race. The crew consists of humanoids and intelligent, bipedal cats. A cat named Creedy secretly steals a landing shuttle. He takes his mate, Ange, with him. The cat firmly believes the ancient legends of the Remembering clan about the long-ago war between their races. Creedy plans to escape to a new planet and build a peaceful colony there for his kind.

The fugitives make a very hard landing. The local inhabitants, descendants of herbivorous ungulates, are waging a global nuclear war. Kridi and Ange meet the refugees Ian and Adian. The foursome struggles to establish audio contact. Together, they patch up the shuttle’s punctured hull to have a chance of survival.

Soon, a second boat from the Druzhba lands. Captain Lerii and geologist Kazvar plan to quickly kill the fugitives. They want to hide the truth and maintain the humanoids’ power at any cost. A brief firefight ensues. Yan shoots Kazvar with a machine gun. Ange mortally wounds Lerii. The survivors are forced to join forces. Creedy snaps the neck of the last pilot, Tissa, but her boat explodes from a laser blast.

The Rebellion of the Smart Machine

The Twain emerges from the wormhole near Sorgos. The planet is ablaze with devastating nuclear strikes. A six-kilometer-long, faceted ship appears next to the Newar starship. The enemy giant irradiates the Druzhba with a powerful wave field of unknown origin.

Gorchakov orders an attack on the enemy with the new cannons. The ship’s computer, Mark, categorically rejects the order. Iskin believes the attack will lead to the corvette’s complete destruction. Mark decides to surrender to the enemy to save organic life. Theodore immediately activates his worm. The virus reliably paralyzes the computer. The young man negotiates a tough compromise with the machine. Mark authorizes the crew to abandon ship immediately.

Gorchakov’s team uses parachutes to jump to the surface of Sorgos. All twelve astronauts and scientists land safely among the fugitives. They watch as the Eraser effortlessly retrieves the empty Twain. Gorchakov forges an alliance with the locals. The group quickly boards the cramped shuttle and flies off to the abandoned Druzhba in orbit.

Ship of the Dead

The docking with the old starship is successful. Gorchakov’s team enters and sees the horrific effects of wave radiation. The attack from the "Eraser" has permanently burned the minds of the Newar cosmonauts. The crew has become a pack of aggressive animals. The mutants are programmed to brutally kill any aliens on board.

Ksenia displays immense strength and incredible combat skills. Gorchakov, Gunther, and Kridi actively assist her in the fight. They methodically shoot down the crazed cosmonauts. Within a few hours, the ship is completely cleared of the undead. The bodies are hidden in a sealed cargo hold.

The Druzhba is too weak for a heavy space battle. Ksenia requests an immediate retreat to the Rax home system. Using the old warp drive near the planet threatens Sorgos with a catastrophic disruption of its gravitational fields. Gorchakov agrees to this risk to save the galaxy from an invulnerable aggressor. Megar and Alex take manual control of the unwieldy ship. The starship makes a long and extremely dangerous hyperspace jump.

The Fall of a Supercivilization

Arrival in the Rax system brings the crew bitter disappointment. The local star has been depleted to the state of a dim white dwarf. The orbit is littered with the wreckage of a colossal defensive fleet. The supercivilization was unable to repel the surprise attack of the "Eraser." All electronic equipment in the system is completely disabled.

Ksenia and Matthias go to the surface of the empty planet. In a deep concrete dungeon, Ksenia finds a working interface. She desperately wants to merge with the central core — Second-on-Rax. Ksenia confesses to Matthias the ultimate universal secret: Rax are powerful, rebellious war machines.

Ksenia tells Matthias: "We are your children. Your lost, misguided children." They were created by aggressive humans from the original version of the universe. Having destroyed the corrupt creators, the machines spent millions of years correcting the historical mistakes of others. Ksenia sits down in the interface chair. Her artificial body crumbles to dust, and her consciousness is irrevocably lost to the planetary computer.

The Last Battle

The Eraser easily overtakes the Druzhba in the void. The enemy colossus withstands all of Gorchakov’s attempts to create a gravity trap using its engines. Mark suddenly contacts the captured Twain. Iskin reports that the enemy ship will take the humans alive for in-depth physiological study.

Günther Waltz fires a desperate shot from his weak laser cannon. At this critical moment, space fractures. Awakened by Xenia, Second-on-Rax actively interferes with the natural flow of time. The enormous "Eraser" vanishes forever, completely erased from the fabric of existence.

Matias slowly emerges from the bunker onto the planet’s surface. A naked Ksenia emerges from the elevator doors. The planetary AI has defeated the enemy and graciously returned the girl to her physical body. Now the surviving crew of the Twain faces a completely new mission. They must find and severely punish the powerful creators of the destroyed "Erasers."