Walking Dead Carol came clean to Tyreese in episode 14 of "The Walking Dead." Photo: AMC

Only three episodes remain in Season 4 of “The Walking Dead,” and the AMC series made sure to pull out all the stops in episode 14, “The Grove.”

“The Grove” kicked off with a mysterious clip that “Walking Dead” viewers have been watching on repeat for the past week – a gas stove boiling water and music playing while a child played outside with a walker. Fans have been dying to know the backstory behind that creepy clip, but it took 20 minutes for the AMC show to reveal what was happening.

So, how did our prison survivors get to that point? Episode 14 strictly focused on Tyreese, Carol, Lizzie, Mika and baby Judith as they continued their journey to Terminus. But like Maggie, Sasha and Bob in episode 13, the group got a little side-tracked with a potential safe haven.

After following the train tracks, the survivors come across a home with a gas tank, water well and small fence. Tired from their journey, and with Tyreese suffering from a fever, the group decides to stay there for a couple of days. An endless supply of pecans and peaches gives Tyreese and Mika hope about finding sanctuary at this new home, but unfortunately that doesn’t end up being the case.

In a dangerous world full of bad humans and deadly walkers, Carol and Tyreese want Lizzie and Mika to remain safe. But the episode revealed that both girls are struggling in this new world.

In the scene from the beginning of “The Grove,” Carol’s frightened to discover that Lizzie is outside playing with a walker. Running outside to get Lizzie away from the zombie, Carol’s shocked to find Lizzie trying to protect it. But that doesn’t stop her from killing the walker.

The death of the zombie sends Lizzie into an uncontrollable meltdown. “I was going to lead her away,” Lizzie yells at Carol.

“She wanted to kill you,” Carol tries to explain to the emotional girl. But Lizzie won’t calm down.

“What if I killed you? What if I killed you?” Lizzie continues to scream. “She was my friend and you killed her.”

Lizzie eventually calms down, but Tyreese, like Carol, now understands that Lizzie has a warped view of the world. And while Mika may not be like Lizzie when it comes to walkers, she does not understand the dangers of the new world. Mika manages to kill walkers when they put her or her new family at risk, but she warns Carol that she won’t kill any humans – threat or no threat.

Carol and Tyreese come to a conclusion that they don’t need to go to Terminus – for now. But their home is not completely safe. Stationed near the train tracks, Lizzie heads back to feed a stuck walker. And when Mika follows her, all hell breaks loose. Mika discovers Lizzie feeding a rat to a walker, and when Mika tells her to stop playing pretend with the zombies, Lizzie completely snaps.

“I can hear them,” she tells her little sister. “They just want me to change … maybe I should change. I can make you all understand.”

Leaning in to let the walker feed off her arm, the pair becomes distracted by a mini hoard of charred zombies (from Beth and Daryl’s cabin fire) heading their way. Screaming and running back to the house, Mike gets stuck in the fence … causing a walker to come dangerously close to feeding on her leg. Lizzie tries to help her sister break loose, but it’s gunshots from Tyreese and Carol that give them enough time to escape to a safe spot. With their brush with death, both Lizzie and Mika join in, successfully helping Tyreese and Carol kill every walker heading their way.

As Tyreese and Carol recover from their close encounter by searching for deer, Tyreese opens up to Carol about Karen … and how he dreams of her every night. “I see someone kill her,” he tells Carol. “Some stranger. And I lose her all over again.”

Carol appears to come close to revealing the details surrounding Karen and David’s brutal death at the prison, but instead she tells Tyreese that people must do what they have to do to survive. And Tyreese agrees, telling Carol to never be ashamed of who she is.

“You did right by those girls,” he continues, giving her a hug. “You did right by everyone.”

But did Carol really do right by the girls? Walking back to their “Grove,” Carol and Tyreese stop dead in their tracks when they spot baby Judith on a blanket outside with a bloody Lizzie beside her. Lizzie has a knife in her hand … and Mika is on the ground behind her.

“Don’t worry,” Lizzie tells Carol and Tyreese of Mika. “She’ll come back. I didn’t hurt her brain.”

Eyeing the baby on the ground, Tyreese and Carol try to get Lizzie to drop the blade. And she does … while whipping out her gun.

“You’ll finally get it,” she says to Carol, telling her that they are going to wait for Mika to wake up. “Judith can change too. I was just …”

With the gun pointing at them, Tyreese and Carol manage to convince Lizzie to put down the gun and to go inside for lunch while Mika changes. But both Tyreese and Carol realize that something more has to be done.

Tyreese puts her in a safe warm with food and reveals to Carol that Lizzie admitted to feeding the walkers and dissecting the rat at the tombs. And even more disturbing than that, Lizzie tells him that “she was just having fun.”

“I was thinking maybe she killed Karen and David,” Tyreese tells Carol. But Carol shakes her head no. “She would have let them turn,” Carol explains. “It wasn’t her.”

So, what do they do with a killer?

“I could leave with her,” Carol suggests. “We can’t sleep with her and Judith under the same roof. She can’t be with other people.”

But Tyreese shoots Carol down, telling her that there must be another way. However, in the end the pair both agree that they won’t make it on their own, and that Lizzie can’t be around other people.

In the morning Carol takes Lizzie outside for a walk to talk and pick wildflowers for Mika. And Lizzie quickly realizes that Carol is upset with her.

“Are you mad at me? Is that what you wanted to talk to me about?” Lizzie asks, beginning to cry. She apologizes for holding a gun up to Carol and begs her to wait for Mika. But Carol tells her that “everything works out the way it’s supposed to.”

Starting to cry as well, Carol tells Lizzie to just look at the flowers. And as Lizzie apologizes and looks at the flowers, Carol shoots her in the head.

Later that night, Carol comes clean to Tyreese about killing Karen and David. “I had to stop the illness from breaking out,” she explains, sliding her gun to him. “I had to stop other people from dying … It wasn’t Lizzie. It wasn’t a stranger. Tyreese, it was me. Do what you have to do.”

“Did she know what was happening?” Tyreese asks. “Was she scared?”

Carol shakes her head no and Tyreese continues with his questions. “It was quick?” he asks, gripping the gun and table.  

“Do what you have to do,” Carol tells him again after confirming that she did it as quickly and as painless as she could.

But Tyreese lets go of the gun. “I forgive you,” he tells her. “I’m never going to forget … you feel it. I know you do. It’s a part of you now. Me too. But I forgive you.”

With tears streaming down her face, Carol thanks him. And both agree that they can’t stay at the “Grove,” and that they have to move on to Terminus.