Inside The Walking Dead Episode 15 — One of the Comic’s Most Memorable Moments

The Kingdom's fair was supposed to be a chance to rebuild the communities and strengthen the bonds between the survivors.

But Lydia's betrayal of the Whisperers sparked Alpha towards a cruel revenge that marred the festivities.

"It really impacts Alpha. We see that she has a vulnerability when it comes to her daughter," says Executive Producer Gale Anne Hurd in a new behind-the-scenes video.

Inside Episode 15

Alpha still chooses to spare Lydia for rejecting her.

But not everyone gets off so lucky.

"Whatever ruthlessness and brutality we've seen before... there's much more coming on the heels of that betrayal," adds Gale.

Alpha has to make the separation between her people and the survivors very clear now.

This time, they won't ever forget.

Click here to hear the cast and creators break down an iconic moment from the comics and share how the communities are dealing with despair in a new way.

Watch the latest episode on and the AMC app for mobile and devices.

The Walking Dead Season Finale airs Sunday at 9/8c on AMC.

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