After serviceman Oleg has a date with Alena, darkness sweeps across the globe. Outside a widening ring around Moscow and pockets in Belarus, Ukraine, and Finland, the lights go out and the fate of billions becomes uncertain. Communications crumble, and only a small band of survivors remains inside what people will later call the Circle of Life. A defensive perimeter is established; reconnaissance groups vanish. What begins as a silent blackout reveals Earth under attack by an unknown foe, with casualties unknown. In response, humanity mobilizes, builds outposts, and fields an army to hold the line. A first reconnaissance team encounters a hostile force that outmaneuvers gunfire and escapes into the darkness.
An outpost loses power, and a massive herd of brown bears storms the defenses. Oleg survives but sustains a severe leg injury. In Moscow, a handful of edge-zone survivors begin to show psychic abilities, and one of them, Sasha, has a direct link to the mysterious attackers. A stranger calling himself Eid appears to Sasha and asks for her help, arguing that her psychic connection can locate Eid's brother Ra, who stands at the center of the upheaval. Four soldiers, led by Marina, pursue Eid, but he wins their trust by displaying his formidable powers and offering to guide them to answers.
Eid explains that his immortal race seeks a new home around a young star, and that thousands of years ago they seeded Earth with a genetically engineered warrior caste designed to wipe out intelligent life. Humanity's weapons proved more effective than the aliens anticipated, driving the invaders to fear. Ra seeded religion to pacify people, but that strategy only fuels violence. Now Ra is mind-controlling humans beyond the Circle of Life to use them as weapons against their own kind, before the alien colony ship arrives. Eid helps Sasha locate Ra, but Ra learns Sasha's location as well. Eid leaves Sasha at the outpost and departs with several soldiers, including Zhenya and Marina, to confront Ra. Marina insists they return to rescue Sasha, but a missile strike destroys the outpost. Eid's willingness to sacrifice teammates causes tension, yet Marina accepts the loss as a necessary sacrifice.
Meanwhile, Yura, a soldier on a separate reconnaissance mission, rescues a young boy. Questioned about the threat, the boy suddenly kills Yura's lieutenant, and the squad terminates the boy. A crowd of mind-controlled people closes in on the squad, and only Yura and Olya survive. They hijack an abandoned car and press on to rejoin a larger unit. On the road they converge with the remaining outpost troops led by Major Dolmatov and the others. Together they move toward Kirov, where Ra is rumored to be waiting. They push through a mob under Ra's influence, fight their way across a skyscraper, and ascend to the roof where Ra awaits. Eid and Ra clash; Eid rips a device from Ra's chest, enabling Yura to shove a grenade into Ra and end his threat.
Eid then eliminates the remaining drones telepathically. He proposes to become humanity's new god, pending the destruction of the alien colonizers. When asked why he did not act earlier, Eid argues that humanity had to be nearly annihilated to force the aliens to reveal themselves and be vulnerable. Fueled by anger, Oleg confronts Eid, while Yura warns that Eid's help is needed. Zhenya tries to stab Eid, but Eid trickily persuades him to kill Marina instead. Oleg and Yura clash over whether to serve Eid, and Olya shoots Yura to end the infighting. Oleg, briefly stunned by a psychic trick, is then shot by Zhenya, who sacrifices himself to kill Eid.
An alien ship descends; the hatch opens and Alena, Olya, and Oleg board it. They discover the aliens are in cryostasis. Countdown timers start, and the trio breaches the ship's oxygen lines, killing the aliens. Yet when they find the last capsules, they realize the aliens' children lie inside. They decide not to shatter the pods. As the timers hit zero, the capsules open and alien children emerge. The humans lay down their weapons, confronted with a stark new choice about whether to harm or protect the next generation of the alien species.
