Part 1: "Can You Hear My Voice?"Aboard a colony ship launched before Earth's collapse, Ok-ju awakens from stasis to find a zombie outbreak has devastated the vessel. Her beloved Muk-ho, who shared a traumatic youth with her, has turned into a zombie. Despite his transformation, Muk-ho refuses to bite Ok-ju and strives to protect her to the end.
Part 2: "Do You Remember My Breath?" On a ruined Earth where survivors live alongside infected family, Jebi cares for an unresponsive mother while struggling to survive. Jebi eventually meets Eun-mi, who raises her developmentally disabled daughter, No-yeon. After Jebi saves Eun-mi, they form a bond, showcasing humanity's enduring will to protect loved ones.
Part 3: "Do You Know Us?" In a world left to zombies and nature, an infected narrator—retaining his consciousness—pushes his zombie wife in a linen cart toward the sea. Guided by her final voice recordings, he journeys to return their pet turtle, Jang-pung,to the ocean.