Kenes, her husband Rudi, and their son Raihan travel to the village of Wanirejo to meet Sadimin, Kenes’s estranged father, and her brother Bambang to talk about selling Wani Waras, the family’s jamu business. The visit is tense from the start, as Kenes harbors resentment toward Sadimin for marrying her best friend, Karina. During the discussion, Sadimin drinks a prototype jamu and dramatically becomes visibly younger, stunning his family. He then announces a drastic shift: he will no longer sell Wani Waras and instead plans to expand by marketing a new jamu he dubs Abadi Nan Jaya. The mood deteriorates into a heated argument, but the situation is interrupted when Sadimin suffers a seizure and collapses.
What follows is chaos as Sadimin reanimates and launches an attack on the household staff, first striking Aris and Pardi, then turning on Bambang, who kills him with a crossbow bolt. The family tries to regroup, with Rudi sending Aris to fetch help from Wanirejo. The moment Aris drives away, he reanimates behind the wheel, crashes into a local celebration at the village chief’s house, and emerges to attack the attendees, triggering a broader outbreak.
Back at Sadimin’s residence, the staff are infected as well. Kenes and Bambang attempt to escape in Kenes’s car, while Rudi, Raihan, Karina, and a maid named Mbok Sum become separated from them. The rest flee toward safety, only to find the village chief’s house overrun by the undead. Rudi manages to contact Kenes and Bambang and reveals their location, but a misstep—Kenes honking her car to signal—draws more attention from the zombies and forces a retreat toward a police station.
Inside a nearby house, the remaining survivors barricade themselves. They are discovered by a reanimated Mbok Sum, whom Rudi kills with a meat cleaver only to discover he has been bitten in the process. Before he can be treated, Rudi bids farewell to Raihan and Karina and then reanimates, ultimately being impaled in the stomach by a metal pump lever and locked away by the house’s owner, Ningsih.
Kenes and Bambang reach the police station and alert the officers, but the station is quickly overwhelmed as the infection spreads among the guards and even the commanding officer. The commander barricades the premises, but is also bitten and reanimates. In the chaos, Rahman and Ningsih’s group realize that the zombies are drawn to sound—an insight sharpened when a mosque is attacked after an adhan call. As night falls, Kenes, Rahman, and Bambang attempt to divert the undead with firecrackers looted from the station, but the horde remains formidable until a heavy rainstorm slows them.
During the chaos, Kenes sneaks into a truck to put distance between herself and the zombies. Rahman and Bambang fall behind and retreat to the station. Taking advantage of the rain, Ningsih and her group maneuver to the station using a motorcycle, hoping to reach safety with the others. They find Kenes in the truck and join in the escape plan. The group reaches the station where Karina, driving the truck, accidentally crashes into the station, pinning Bambang and letting zombies flood in.
In this dire moment, Ningsih is bitten by the station’s reanimated commander while trying to help, and Rahman shoots the now-reanimated Rudi. The remaining trio—Raihan, Karina, and Kenes—try to pull Bambang from the wreckage, but the situation looks hopeless. Bambang urges them to leave and detonates a supply of firecrackers to ignite leaking gasoline, causing a massive explosion that destroys the station and wipes out most of the surrounding zombies. It is revealed that Kenes had also been bitten; she uses flares to lure the undead away and then shoots herself in the head, sacrificing herself so that Karina and Raihan can escape on a motorcycle as the horde pursues.
In a mid-credits moment, the film’s global danger continues: Sadimin’s business partners in Jakarta, Santoso and Grace, fail to contact him and then witness Grace ingest a vial of Abadi Nan Jaya, which begins to make her younger, a hint that the new jamu’s effects extend beyond Wanirejo. Grace presents the transformation to Santoso, signaling that the threat may be far from over.