The Most Sad, Shocking and Brutal 'Walking Dead' Deaths So Far

Also, Thora Birch -- aka Dani from "Hocus Pocus" -- joins the cast in a creepy new role.

Ever since Alpha and Beta arrived on "The Walking Dead," we really wanted to know how these two crazy kids met. Tonight, we learned just that, as the AMC series devoted an entire episode to the Whisperer queen and her right hand man.

The narrative was split between the present day and their first encounter with each other seven years before. For recap purposes, we're going to break this down chronologically, beginning with the backstory.

"We Are the End of the World" began with Alpha (Samantha Morton) and a young Lydia on their own, watching a woman get devoured by walkers as they shuffled along with them, covered in blood and grime. After one of Lydia's screams put the zombies on their tail, they run and hideout in a nearby building -- one we later learn is the Second Lives Treatment facility, a rehab center.

Waiting for them inside was a beast of a man with a ski mask over his face, totally not creepy at all. We don't know his name initially, but he's the man who we'll later know as Beta (Ryan Hurst). While he wasn't much of a talker, he allowed the two to stay in the facility overnight.

At this point, Alpha has already retired whatever name she was given at birth and no longer wants her daughter to call her mom. "The dead don't have names and we shouldn't either," she said to her new roomie. "Those of us who are strong enough to still be alive out here know each other on a primal level."

Before bed, Alpha told Lydia she needs to get her act together and fast -- or she'll "have no choice but to leave you behind." As her daughter slept, Alpha wandered the halls, ran into some zombies and went on a killing spree with her future-sidekick. Post-slaughter, they have a conversation which leads to their nicknames after she calls him "Big Man," and then "Mr. B."

"[Mr. B is] not a name, it's a letter," she says. "If I'm B, what does that make you?" he asks. Her answer: "A." At some point, they decided to go Greek with it.

She also filled him in on why she likes to walk with the walkers -- explaining that it's not simply about blending in to survive. "You gotta become them. Feel what they feel," she told him. "There are only two kinds of people left in this world. The ones brave enough to walk with the dead and everybody else."

Wandering into Beta's wing of the hospital looking for Lydia later, she saw a photo behind a display case with two faces scratched out, showing Beta was apparently a patient there. A walker emerges and she kills it, only to later realize that zombie was the other person in the photo -- and a close friend of Beta's that he'd been keeping "alive."

After his freakout over the death, Alpha invited him to "walk with me in the darkness" so he'll "never be alone again." While he was hesitant about leaving his friend behind, Alpha told him he doesn't have to, handing him a knife. Yep, Beta's mask is the face of his dead best friend -- how sweet, right?

Flash forward seven years and Beta is on a mission to round up more walkers for their horde with a pair of sisters, Frances and Mary (Thora Birch). Frances is the mother of the Whisperer baby that was left on the ground outside of Hilltop -- and her decision to follow Alpha's orders and leave the child behind is clearly haunting her.

Beta and the rest of Alpha's followers want to kill her, as she keeps freaking out and crying about what she's done. She's also in the dog house for saying out loud, "He's with them in a better place," suggesting the lives of the other survivors are great in comparison to their own. This doesn't please Beta.

"The others have already spoken of the enemy, the life they saw," he warned Alpha, worrying their followers will lose faith. "It is not a life, it is a fantasy," she reminded him. Then, instead of punishing the woman, Alpha took her aside and gave her a space to cry in and grieve, all while stroking her hair. Beta doesn't love this either.

Unfortunately for Frances, she had another freak out, this time in front of Alpha. As the walkers in their herd closed in, Mary sacrificed Frances -- her own sister -- to save their leader. When asked later if she has any regrets over what she did, Mary had none, simply calling her own sister "uncommitted."

Alpha was all about this answer, saying "we are strongest when we kill our own blood" and anointing Mary "Gamma." This, also, doesn't sit well with Beta.

Though Alpha and Beta appear to be on totally different pages in the present day -- something that could end up biting Alpha in the butt down the line -- they do come together again in the end with a creepy ass pow wow repeating their personal mantra.

"We walk in darkness, we are free. We bathe in blood, we are free. We love nothing, we are free. We fear nothing, we are free. We need no words, we are free. We embrace our death, we are free. This is the end of the world. Now is the end of the world. We are the end of the world."

The episode ended with them seeing the smoke from the fire the other survivors put out. Realizing it was on their land, they vowed to "teach them a lesson," while also getting their own group back right on track.

The last shot: Alpha seeing Carol (Melissa McBride).

Yes, "The Walking Dead" is clearly setting up a big showdown between these two women -- but this episode hinted at a possible split between Alpha and Beta as well. If she continues to lean on Gamma, diminish Beta's role at the top and ignore his advice, she could have an enemy within her own house.

"The Walking Dead" airs Sundays on AMC.

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