The alien species known as the Kulku launch a chilling demand: eight million humans must be handed over to them so they can extract a cure for a deadly virus ravaging their world. In exchange for this grim quota, the Kulku promise not to wipe out Earth. As nations scramble to respond, some release prisoners to meet the demand, while the United States opts for a nationwide lottery. Among the chosen is Heather, the daughter of Dr. Stephen Chase, thrusting a deeply personal stake into a planetary crisis. Dr. Chase, driven by a mix of family resolve and scientific purpose, joins the human resistance, dedicating himself to sabotaging the Kulku’s plan and killing as many invaders as he can. The resistance, bolstered by Chase’s weapon designs, achieves some early momentum, but Heather is captured and taken aboard the Kulku mothership, where a startling revelation emerges: a small portion of Heather’s blood is enough to cure a Kulku, not the entire supply as with other humans.
As the Kulku intensify their harvesting, Jal, the Kulku ambassador, lays out a treacherous path. He intends to move Heather to Kulku space and, with the aid of the Raeg weapon, destroy Earth so she can depart for the Kulku homeworld as a celebrated figure. In the meantime, the U.S. Army, led by a wary Major General Skyler who has shifted from foe to ally, joins forces with the resistance in a bid to halt the invasion. A modified weapon, mounted on a telescope at a remote observatory, becomes the key instrument in their plan to annihilate the Raeg. The plan hinges on timing and trust, but a traitor within their ranks alerts Kor, a Kulku who shows sympathy for humanity but refuses to betray his own people. Kor lands a strike team at the observatory to stop the resistance, and Chase takes a bold chance, boarding Kor’s ship to reach the Kulku mothership and rescue Heather.
Inside the Kulku stronghold, Chase and Heather uncover a brutal reality: Jal has already slaughtered most of his own kind in a bid to return home as a hero with Heather in tow. Jal gravely wounds Kor and engages Chase in a clash of wills and wits, while Heather’s quick thinking creates a distraction that turns the tide in favor of Chase, who kills Jal in a decisive confrontation. With Kor gravely wounded and seeking survival for his species, he attempts to trigger a final, desperate detonation of the Raeg. Back at the observatory, the battle rages on as two Kulku and several resistance fighters fall. The weapon nears readiness, but two remaining Kulku nearly slay Blair before General Skyler and his soldiers arrive to finish them off. Blair fires the weapon, destroying the Raeg in a spectacular and crucial moment. Kor’s wound continues to worsen, and in a final act of vengeance, Heather brings him down, ensuring he cannot menace Earth again.
Chase pilots a Kulku shuttle back to the observatory, where he and Heather reunite with Blair and General Skyler. A grim closing broadcasts reveal that nearly eight million people lost their lives to the Kulku invasion, and the world begins the long, difficult process of recovery. The Kulku themselves are left to confront a virus with no known cure on their own homeworld, implying a grim fate for their species as Earth begins its slow return to stability and peace.
