Last week's episode "Them" featured the now-iconic line uttered by Rick while the group were hunkered down in the barn. When all hope seemed lost and the group were in the depths of despair, he said:
"This is how we survive. We tell ourselves that we are the walking dead."
Then, with the walkers threatening to break in and devour everything in their path, the group came together to repel the threat at their door.
It was an incredibly powerful moment...
You know what's even more kick-ass about this scene? It was a direct reference and excellent bookend to an event that occurred earlier in the show's history.
An event that also involved a barn and the undead. But this time the walkers were trying to get out, not in.
And one of them was a little girl called Sophia...
If you cast your minds back to Season 2 and the episode entitled "Pretty Much Dead Already" the gang are on Hershel's farm, and suffering quite badly from an undead problem.
You see, back then, Hershel believed the walkers were still people and that there was going to be a time in the future when a cure was available and they could become human again.
However, Rick and Shane put bullets in rotters brains and dispelled that little theory.
Fast forward to last Sunday's episode and the reverse has occurred. Rick believes that they themselves are now the walking dead and embracing this is the only way to survive.
But Daryl won't let that fly, shooting back with "we ain't them."
And you know what, he was soon proved right. At the depths of their despair, when it seemed they were no more human than the rotting, walking corpses at the door, they suddenly rediscovered their humanity. They came together and worked as one to defeat the dead at their door.
Just as back in Season 2 massacre of the walkers coming out of the barn proved to Hershel that they were different to the undead, the walkers trying to break in to the barn in "Them" proved to the group they were still different to the undead, that they were still human.
It was a beautiful piece of symmetry and an excellent callback. Well played The Walking Dead. Well played indeed.