Plot

The focus is on the sleepy small town of Centerville where the dead become undead.

As the warm, bright sun refuses to set, and a series of equally perplexing events start to take place, the world, and the blissfully unsuspecting residents of the sleepy town of Centerville, are about to face the effects of corporate greed. Then, as the stone-faced police officers, Chief Cliff Robertson and Officer Ronnie Peterson, stop for doughnuts and coffee at the town's diner, unusual activity in the moon-lit cemetery and a blood-soaked scene of carnage could only mean one thing: this is the work of flesh-eating zombies. Before long, Officer Mindy Morrison and the glacially beautiful, katana-wielding undertaker, Zelda Winston, join the team of defenders, as hordes of relentless, ravenous undead swarm into the once-peaceful town craving meat. More and more, humans are at risk of becoming an endangered species. What happens when the dead just don't want to die?—Nick Riganas

Responding to a complaint from farmer Frank Miller (Steve Buscemi) regarding a missing chicken, small rural town Centerville police officers Cliff Robertson (Bill Murray) and Ronnie Peterson (Adam Driver) briefly confront local eccentric Hermit Bob (Tom Waits) in the woods. On their drive back to the station, Cliff remarks that it is still daylight after 8 pm while Ronnie notices his watch and cell phone have stopped working. Farmer Miller talks about Hermit Bob with hardware store owner Hank Thompson (Danny Glover) at the local diner. Hank hears a worrisome radio report about polar fracking. Hank and diner waitress Fern (Eszter Balint) also wonder why it is not dark outside. A song called "The Dead Don't Die" plays on the radio, which Ronnie tells Cliff is the theme song.

Following a news report seen at the Centerville Juvenile Detention Center, Geronimo (Jahi Winston) tells fellow young inmates Olivia (Taliyah Whitaker) and Stella (Maya Delmont) that polar fracking has altered the Earth's rotation. Deliveryman Dean drops off rare magazines with gas station owner Bobby, who also sells pop culture memorabilia out of his store. Moonlight Motel owner Danny Perkins (Larry Fessenden) watches broadcaster Posie Juarez's (Rosie Perez) news report about pets behaving strangely, and his cats are missing. Farmer Miller also notices that his farm's animals have disappeared.

Cliff and Ronnie regroup with Mindy Morrison (Chloë Sevigny) at the police station. The three officers discuss the strangeness around Centerville. At the diner, the waitress tells her customer Hank about Zelda Winston (Tilda Swinton), the odd new undertaker at the Ever After funeral home. Lily (Rosal Colon) is Fern's cleaner at the diner

Meanwhile, Zelda practices her sword skills in front of a Buddha statue in the funeral parlor. Two zombies obsessed with coffee reanimate when night finally falls and maul the two diner workers inside the diner. Hank summons Cliff, Ronnie, and Mindy to the diner when he discovers the bodies in the morning. Ronnie tells Cliff he believes zombies slaughtered them.

Zoe (Selena Gomez) and her traveling companions Jack (Austin Butler) and Zach (Luka Sabbat) stop for fuel at Bobby's gas station. After buying Sturgill Simpson's "The Dead Don't Die" compact disc from Bobby, they check into Danny's Moonlight Motel. Cliff and Ronnie discuss the diner murders with Danny. The two officers meet Zoe, Jack, and Zach while at the motel and tell them to not go out at night. Olivia, Stella, and Geronimo also discuss the diner murders at the juvenile detention center. Geronimo suggests an impending zombie apocalypse is responsible for the deaths.

Cliff and Ronnie find open graves when they investigate the cemetery. Hermit Bob spies on the men from a distance before separately concluding zombies are loose. Ronnie gives Cliff guidance on how to kill zombies. Bobby and Hank have a similar conversation as they prepare weaponry. More zombies rise from the dead that evening. Danny is attacked at his motel and turns Undead. Zoe, Jack, and Zach lock themselves in their room after a Posie Juarez news bulletin warns them of the danger.

Cliff and Ronnie bring supplies back to the police station and tell Mindy about the zombies. Mallory O'Brien reanimates. Ronnie decapitates Mallory. Two corpses reanimate inside the funeral home. Zelda beheads them with her sword. Zelda then meets with Cliff, Ronnie, and Mindy and offers help. The three officers leave Zelda at the station while they go out on patrol together. leaving Zelda alone to send an encrypted computer message using their computer. Cliff, Ronnie, and Mindy find Zoe and her friends dead when they investigate the motel. Ronnie beheads all three bodies to prevent them from reanimating. Ronnie takes Zoe's Sturgill Simpson CD, which has played numerous times during the movie, and Cliff throws it out of the car window.

Hank and Bobby are overrun by zombies in the hardware store. Hermit Bob sees zombies mauling Farmer Miller. Geronimo, Olivia, and Stella flee the juvenile detention center. Zombies surround the patrol car when it gets stuck at the cemetery. Mindy runs out of the vehicle to join her dead grandmother in the zombie horde. Ronnie tells Cliff he knew it would end badly, because Jim gave him the entire script.

Zelda takes Ronnie's car through town and then walks calmly through the cemetery. Zombies amble away from the patrol car as a spinning UFO suddenly hovers over Centerville Cemetery. Cliff and Ronnie are astonished as the UFO beams up Zelda and flies away. Cliff and Ronnie decide to go on the attack, as Ronnie says it is in the script. The two officers exit their car and begin killing Undead Centerville residents including Bobby, Farmer Miller, and Danny. Cliff becomes upset when he sees Ronnie behead Mindy. Zombies eventually overwhelm Cliff and Ronnie. Hermit Bob observes the fray from the woods through binoculars while commenting in voice over, quoting Melville and lamenting the world is a terrible place.