Sunday's episode of The Walking Dead, "The Other Side," likely set up the death of Sasha Williams (Sonequa Martin-Green), the survivor who arrived at the prison in Season 3 and remained strong even as she lost everyone she loved.

Sasha and Rosita (Christian Serratos) went on a rogue mission to assassinate Negan (Jeffrey Dean Morgan) as revenge for killing Abraham (Michael Cudlitz), the man they both loved. Sasha had already told Rosita she was going to take the shot at Negan, but in "The Other Side" she showed that she meant she was going to do it alone. She locked Rosita out of the Sanctuary and charged in solo after making peace with Rosita and telling the younger woman that she was too important to the group to die.

TVGuide.com caught up with the very busy Martin-Green (she's a lead on the upcoming series Star Trek: Discovery) over email to talk about Sasha's decision.

Sonequa Martin-Green,<em> The Walking Dead</em>Sonequa Martin-Green, The Walking Dead

So obviously the big question, besides "Is this the end of Sasha?" is why she did it. What was Sasha's thought process when she locked Rosita out and went in alone? Did she always know she was going to do that or was it an impulsive decision?
Sonequa Martin-Green: As Sasha, I feel like I've been enlightened to my true identity. I've realized that real strength is not the ability to just survive but the ability to sacrifice in love and for love. All roads have led me here, and I'll do anything to right this wrong and build the future we deserve. One not perverted by Negan and what he represents. I feel like our family, and the whole world, needs me to do this. I realize after our reconciliation that there would be no point to her sacrificing as well because she's needed for so many other reasons. This is my path, not hers, which is what I mean when I say to her at the gate, "There's gotta be a point to it, right?"

Was Sasha's attempt to bond with Rosita her way of settling any lingering, let's say "karmic debt" in case she doesn't make it out? Why would that be important for her to do?
Martin-Green:
I needed to bond with her because our success depends on it. The air has to be clear between us to see what's ahead of us clearly. Honestly I think the very fact that we've embarked on this mission together speaks volumes of our potential. And more intimately, I've been holding onto so much guilt for how she was hurt from mine and Abraham's relationship. I needed her forgiveness because I don't want to tolerate those self-condemning thoughts anymore. I've been there, done that and grown past it.

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What's Sasha's take on the Eugene situation? It kind of seemed like she was so focused on the task at hand that she wasn't even thinking about whether he's Negan or not.
Martin-Green:
Well I'm definitely focused because the chance to take the shot at Negan was so very close. And that focus doesn't break because I have the same take that Rosita does, that Eugene is most likely playing an angle. I'm skeptical of what it looks like, sure, but I don't imagine that he's done an about-face.

This was a bad plan, right? When you were reading the scripts, were you like "Sasha, Rosita, what are you doing?"
Martin-Green:
Not at all. I think it's something that any of us could be driven to at this point. We suffered a lasting trauma when we were all together on our knees, so all the more motivation to limit risk and go at it as a duo. Going alone would be irrational, which you see me realizing in the teaser of the episode. But Rosita delivers the key to success, [with] her presence and skill, and the sniper rifle. That's how this mission makes sense.

The Walking Dead airs Sundays at 9/8c on AMC.