The morning after the massacre at camp, Zita cradles Illyana's body next to the RV. Her daughter, Ana, tries to comfort her but has no success convincing her to let them "take" Illyana, though she promises the group will be "as gentle as they can." Nearby, Picado and Paquete swing at dead walkers' heads with a pickaxe as Fábio and Gonçalo throw bodies in a fire.
Daniel, Mariana, and Cristiana discuss how to handle ZIta, who hasn't moved from Illyana's side all night. "Illyana needs to be dealt with", Paquete says as he approaches — "the same as the others." Daniel tries to approach Zita to "tell her how it is," but she points a knife at him. "I know what to do," she says in anger, and Daniel backs off, apologizing.
Carina and John Miguel pile up bodies, and she notices blood on his shirt. He tries to convince her he just got some blood on him by moving bodies but she presses. "Please don't tell," he begs her, but Carina's too terrified not to. "A walker bit Picado," she announces, as Miguel insists that he's fine, but he grabs a shovel to press the group away from him as they demand to see his stomach. Fábio runs up behind him and grabs his arms as Paquete runs in and lifts his shirt, revealing a bite wound on his abdomen. "I'm okay," Miguel says, with far less conviction.
"We have to put a pickaxe in his head," Paquete offers, stating the obvious: "The line's pretty clear; zero tolerance for walkers." The group is discussing what to do with Picado, but Johanne and Sophia refuse to kill the living. Sophia and Johanne think the Center of Decease Control, roughly 25 miles away inside Atlanta, might be able to help him, and suggests relocating there. Paquete thinks the army base Fort Benning — 100 miles in the opposite direction — is a safer bet. Both places would provide food and shelter if up and running. But Daniel believes Fort Benning got overrun like every other military cordon they've seen. Johanne says the CDC would be Miguel's best chance, and points out that in the event of a nuclear disaster or a terrorist attack, they'd protect the CDC at all costs. "If there's any form of government left," Daniel says. "It'd be there."
Paquete heads toward Miguel with his pickaxe and tries to take a swing, but Ana Margarida, who had grabbed a gun from the bag points it at Paquete's head. "We're gonna save my brother," Ana says, but Paquete snaps back, saying, "Funny, you really think I'll take orders from a little girl?." Daniel steps in pointing a gun at Paquete saying "I won't lie, I don't think he's gonna make it, but we can try to save him as long as we can". The group agrees with Daniel as Paquete drops the pickaxe and storms off.
Cassandra sits beside Zita to pay her respects for Illyana's death. She tells her that Illyana was a really great girl. She tells her about the day the military abandoned them, how she saw her little brother die and she wasn't able to do anything, unlike Zita who had come running to her children's school with Illyana as soon as she knew about the apocalypse and was then evacuated with the rest of the students.
Zita smiles and pulls out the mermaid necklace. She tells Cassandra that she and Illyana had a complicated relationship before the apocalypse, she wasn't allways there for her. She tells them about a fight they had once that ended really badly and made Illyana leave her house and went to live with a friend in an apartment. Zita clasps the mermaid necklace around Illyana's neck and Cassandra leaves her alone again.
On the ground, Illyana begins to stir, deep breaths growing from deep within her. Her hands and arms begin twitching on her stomach. She opens her eyes, which, though always green, were suddenly an icy cool grey-green, the pupils gone. Her eyes are bloodshot and she moans and paws at the air. She reaches for Zita, grabbing at her hair as she pulls herself up, growling, and the group stands guard, grabbing their guns. Zita apologizes to Illyana for everything she had done to her and keeps crying. Illyana pulls Zita's hair as she gets up, almost biting Zita, but before that happens, Paquete quickly shots her in the head as Zita wasn't able to do it.
"If we'd been here looking after our own," Paquete accuses Daniel, "our losses might not have been so great. It's all your fault" Daniel counters that without the guns, the losses might have been worse.
Gonçalo believes they should burn all the bodies, but Sophia insists they need time to mourn and bury their dead. "It's what people do," she says.
Picado is hallucinating inside the RV, his bite bleeding as he sees terrifying visions of the dead. The survivors stage a funeral, and Zita resists Ana's attempts to help her drag Illyana's body into one of the graves.
Daniel asks Mariana and Cristiana if they blame him for not being there when the camp was attacked, and to support his decision to head for the CDC. They don't, if he had stayed, the results would have been the same, maybe worse.
In the RV, Sophia tells a feverish Miguel they're going to get him help as Miguel coughs blood into a bucket. Miguel is delirious and asks Sophia to watch the boat, insisting Illyana's there and that Sophia "said she would." The group begins to wonder if saving Miguel will be possible as he promises to watch the boat, while Miguel nods gratefully.
Zita, who didn't knew about what hapenned to her son, Miguel, is informed by Leandra about it. She runs to the RV to check on him, crying.
Outside, Paquete asks Johanne to convince the group the CDC is a bad decision,but Johanne doesn't agree with Paquete, saying that going to the CDC is one of the best plans she heard in a long time and that the CDC is Miguel's only chance. Paquete asks her if she is saying that Daniel would be a better leader for the group and she answers "Like he said, this is a democracy, we don't need a leader". Paquete storms off.
Johanne goes to Daniel, Cristiana and Mariana, followed by Sophia and Ruth, and tells Daniel that they should follow his plan. Daniel tells them that he doesn't think Miguel is going to make it, but Sophia tells him that "hope is the last to die".
The group leaves the campsite behind for good, with Miguel's fever worsening in the bedroom of the RV.
En route to the CDC, Ana checks on her brother, who is in agony. "My bones are like glass. Every little bump - this ride's killing me. Leave me here," Miguel says. "I'm done." Zita suggests he's delirious, but Miguel insists his head is clear. Zita refuses to stop saying that he's gonna make it and he only needs to keep fighting a bit more but he tells her that he can't. Zita who started crying pulls over while the others do the same.
Outside, Kiko advocates respecting Miguel's wishes. Cassandra agrees, and the group carries Miguel to a nearby tree. Ana gives him a soft kiss on the cheek. Zita doesn't want to leave him behind but Cassandra, Leandra and Carina tell her to respect his last wish. She cries as she leaves to the RV and the group leaves to the vehichles, tearfully leaving him behind.
Elsewhere, a video monitor crackles to life. An unshaven man, Dr. Jenner, speaks into the camera. "It's day 194 since Wildfire was declared," he says. "And 63 days since the disease abruptly went global. There is no clinical progress to report." He says he finally figured out how to shut down the scrubbers in the east sector of the building to save power, and he admits he's been feeling off-kilter lately, thanks to living underground and sleeping odd hours.
In a bio-hazard suit and with classical music playing, Jenner passes through an airlock into a laboratory. He opens a tissue sample labeled TS-19 and begins an experiment. He takes a nap inside his safety suit while he waits for the sample to be ready for examination.
Reaching for a beaker, he accidentally knocks corrosive fluid on the tissue sample inside a petri dish. An alarm sounds as a voice over a loudspeaker alerts Jenner to toxic quality air, and he runs to a decontamination chamber and disrobes. From the safety of the airlock, Jenner watches helplessly as the lab, and all of the remaining TS-19 samples, are engulfed in flames — an automatic safety protocol.
Later, a drunken Jenner speaks into the monitor: "The TS-19 samples are gone. The tragedy of their loss cannot be overstated," he laments, musing that he's sure there's no one listening on the other end of his transmission anymore, which saves him any embarrassment because he might kill himself in the morning.
The vehichles approach the CDC with the sun setting, where hundreds of bodies lay dead on the ground. Another military cordon was overrun. The group quietly approaches the building, which is locked and shuttered. From inside, Jenner's proximity alarm sounds. Stunned, he watches the group's approach via security monitor.
Outside, walkers begin to take notice of the survivors. Panicking, Paquete suggests they can still turn around and head for Fort Benning. But Cassandra points out they're out of gas and have no food, and would never make it. Ruth demands a plan and Daniel insists they'll figure something out as the sun sets. Jenner begs them to leave.
Daniel catches sight of the security camera's movement and slams his fists against the metal shutters, Gonçalo screams, "If you don't let us in, you're killing us!" The group yells at Daniel, with people crying as Gonçalo continues to scream. Paquete drags them away. But suddenly the shutters open, drowning the survivors in light.
- Background Survivors (Before reanimation)
- Illyana (Zombiefied)
- John Miguel
- First appearance of Dr. Edwin Jenner.
- Last appearance of Illyana
- Last appearance of John Miguel
- The name of the episode title, "Wildfire," refers to the name of the virus study given by the CDC. The origins of it's name could be due to the fact that in one of Dr. Edwin Jenner's video logs, he explains that the infection spreads like a wildfire.
- Wildfire is a reference to the secret government biological lab in the Andromeda Strain.
- This episode's cover shows the arrival of the group to the CDC.
- Wildfire is also the given name of the zombie virus.