Warning: Possible spoilers ahead.

The Ricktatorship is alive and Ricktatoring. In one of the more surprising moments of "The Walking Dead" so far, Rick Grimes banished admitted murderer Carol from the prison group in Sunday's "Indifference."

With the idea of safety-in-numbers clearly taking a back seat to Rick's bigger concerns — like whether or not Carol could be trusted not to kill others, including Rick's children — at the infection-overrun jail, "The Walking Dead" executive producer Gale Anne Hurd talked to Yahoo TV about Sunday night's episode, and reiterated a warning offered by series stars like Andrew Lincoln and Norman Reedus: There are lots more twists ahead, and you will not see them coming. "I assure you of that," Hurd says.

[Related: Most Shocking 'Walking Dead' Moments So Far]

This episode, with Rick's big decision about Carol, felt as monumental, as game changing, as some of the big character deaths.

Yes. We do tend to make our fourth episode of the season … it's become sort of a tradition that something explosive happens in the fourth episode. Last season it was Lori dying and T Dog dying. This season it's equally monumental, but just in a completely different way.

Did Rick know when he left the prison with Carol on the supply run that he wasn't going to bring her back?

I think he wanted to see how she handled it. Was she regretful, was she repentant [about killing Karen and David], or is she someone that it might be dangerous to have around? I think he was using their reconnaissance trip to feel her out. At the same time, he has, up until this point, abdicated power to the council. Of course, with the outbreak of the virus, a lot of the people on the council are sick. And she was on the council. It may be that Rick will have to revert to making decisions on his own.

What do you think was the one moment that pushed him into the decision?

I think there were a number. One of them, I think, though, was when she was so eager to just leave [Sam and Ana], the two new people that they encountered behind, and basically said, "They're not here. Let's leave." [He begins to wonder] if Carol has become so heartless that she might make a decision that would end in one of his family members' or other friends' loss of life? Has this brutal world created someone incredibly callous in Carol, the person who was certainly one of the most almost touchy-feely people, and certainly someone who, up until the zombie apocalypse, was a victim?

He has to weigh all that in his mind. Is she someone who's going to be safe to leave Judith with? Is she someone that he can entrust Carl to? It's a delicate balance between making good decisions and tough decisions, and making the wrong decisions.

The cast and crew break down the fourth episode, "Indifference":

The watch seemed to be a key thing, too. Carol gave Rick her watch not as a memento, but because she assumed the reason he was so upset about Sam's death was because Sam had his watch …

Right, which is, of course, not it at all. In her mind, at this point, I think we're getting the sense that practical decisions become almost more important than human life. Human life is only valuable … she thinks there's a certain point at which you just cut bait.

And yet, on one level, on a purely survival level, you can understand her justification for what she did, up to a point.

Of course. If you think about it, if it had worked, if the illness had been stopped in its tracks because she'd killed Karen and David, you'd be looking back on it a lot differently, maybe. Or maybe not, but the truth is, it didn't work. In retrospect, it certainly was not only the wrong move, but indefensible.

Carol accepted Rick's decision to banish her from the prison fairly quickly and easily, even after he told her she couldn't take Lizzie and Micah with her. Did she maybe agree a little too quickly, a little too easily? Maybe this isn't the end of Carol's time with the group?

She also answered very quickly when he asked if she was responsible for the deaths back in ["Isolation"]. She's become a real pragmatist. I don't think she's going to spend a lot of effort defending her actions or arguing. She understood at the time that there could very well be repercussions, and that they would be severe.