[WARNING: The following story contains spoilers about Thursday's episode of Scandal. Read at your own risk.]

Alex promised Olivia he'd give good dirt on Susan on Scandal — and it was.

The contents of that folder that left Liv (Kerry Washington) all flustered were revealed on Thursday's Scott Foley-helmed episode: Susan (Artemis Pebdani) had an affair years ago and conceived her daughter, Casey, whom she has been passing off as her late husband John's. Even juicier: She wasn't married to John. The juiciest: Casey's father, Ronnie, is currently in prison.

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Complicating matters is Susan's last-minute comeback in the debate with a stirring speech about — yup — John, who was killed while serving overseas and whom she had wanted to tell to come home. "We are not our husbands' keepers, but maybe we should be America's," she says to rapturous applause, which sends a frantic Mellie (Bellamy Young) to do "Mean Tweets" on Jimmy Kimmel Live! to endear herself to the public.

Obviously Liv wants to air all of Susan's dirty laundry and get Ronnie to talk in order to knock her out of the presidential race, but Fitz (Tony Goldwyn) pleads with her to run a clean campaign. He gives Susan a heads up and during their heart-to-heart, reveals all about Defiance and all the duplicitous means behind his election. Just as Susan makes up her mind as to whether or not to come clean to the public, news breaks that Ronnie has hanged himself in prison. But was it really a suicide or the work of Rowan (Joe Morton), who's pissed Liv gave Alex (Danny Pino) the apparently false rehab scoop on Edison?

We chatted with Pebdani about Susan's big secret, if her "prop" beau David (Joshua Malina) will ever find out, and if she'll ever find out that Liz (Portia de Rossi) was David's other woman.

What was your reaction when you found out Susan's secret?
Artemis Pebdani:
I found out, like all the actors find out, at the table read. We find out as we're reading. Honestly, it was such a huge shock. This story she had for her daughter and everything she built up to protect the memory of her husband has been so ingrained — it's part of how she runs [her campaign] and her support of the troops. It's so who she is. It was a huge shock to me to find out she cheated on her husband at all, but I totally understood why she did that to protect her daughter.

So you weren't aware when you did the scene last week when she asked Fitz about why people have affairs. Now that takes on a whole new meaning.
Pebdani:
Yeah, oh, that's such a good point! So much many of the episodes, that happens, where retrospectively things take on a whole different life. Good point, Joyce. You can put in there I said that!

I will then! Susan was bailed out when Ronnie died at the end, but do you think she was going to come clean? How were you playing it?
Pebdani:
I go back and forth on it. But Artemis thinks that Susan wasn't going to come clean. As morally centered as she is, I think protecting her daughter trumps everything. All of us have that soft spot — that Achilles' heel — and she couldn't do it. She just couldn't expose herself. She made it this far. She's made it 10 years into her daughter's life. That's telling her daughter she's lied this entire time and God knows what other lies she's told her daughter. That's her weakness. She just can't.

You think her reasoning is more personal than politically based. It's not just because she's running for president.
Pebdani:
From my point of view, everything at her core, everything Susan does is for her daughter. That's my point of view from Day 1. Running a presidential campaign is so much stress on home life and everything. It's all to make the world a better place for her daughter, so that's how you can excuse that. That's how you can excuse being away from her daughter for so long. It's because you're making the world a better place for your daughter. I think that trumps all political aspirations.

Ronnie supposedly committed suicide, but it's implied that Rowan killed him. Do we find out how he died?
Pebdani:
To tell you the truth, I don't remember if we find out or not. I think I always personally assume if someone dies, Rowan did it. [Laughs] It's kind of where I go.

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He's nice to have handy in situations like this. Her secret's still safe for now.
Pebdani:
Oh, my gosh! I would love and be terrified to have a friend like him. So valuable!

How is Susan going to be affected by this whole ordeal?
Pebdani:
It's almost in a weird way, like, being in the club now. She is in the club. Everybody depends on everybody else to keep their secrets. She knows [Fitz's] secrets now. It's this weird sort of codependent support of keeping the worst parts of yourself tamped down, and everybody supporting you. What a dark world in politics! [Laughs]

Do you like that she's part of the club? Susan was one of the few characters who was not wholesome, but clean. There was no dirt on her until now. Now's she's kind of corrupted.
Pebdani:
Yeah, it's such huge pressure, 'Oh, she's the moral center.' Not for me, but I think for Susan, what huge pressure. Nobody's perfect. Nobody has nothing going on in their lives where they've done nothing wrong. It's a relief she's a real person with a real history. She has an imperfect past like everyone else. I'm down with it!

Is David or anyone else going to find out? Is she going to tell David?
Pebdani:
Oh, right. Good question! I guess no at this point. She doesn't owe anything to David.

She can hold him cheating on her over his head forever.
Pebdani:
Oh, yeah. That's adult treachery. I don't think she needs to tell him anything. He doesn't deserve to know anything, especially not now.

He confessed his love for her last week. Does she feel the same way?
Pebdani:
I think she did feel the same way. Once you've been hurt, once you've been cut that deeply, it's just so hard to come back from.

She and David still have to pretend to be a couple. How is that going to work out?
Pebdani:
Oh, my gosh! I can't even imagine what that's like. Every day you have to get up and kind of live this lie for everybody to see. You go to sleep knowing you have to wake up again and live that lie. This also part of Susan being in the club. Now she's going to have to play this game. This game - if I want to be president, she can't completely absolve herself of everything icky or gross. There is a certain level of nasty that she's just going to have to be part of.

Is Susan's head totally in the campaign now? She was off her game last week with the David stuff, but now after winning the debate and with Ronnie dead, is she emboldened to go all in?
Pebdani:
I think there's still the residual ickiness — when you break up with someone, that is still in you. It's still swimming around in your. But man, it's so much easier to function when love's not messing it up! ... I think now it's all in. She's all in in the game. As long as she has Liz North by her side, her own Cyrus Beene. No offense to Liz North, but that's her Rowan. With that sort of tiger by her side, why not? I would think I was invincible too?

Is she going to find out Liz is the other woman?
Pebdani:
I don't know. I don't know! I wonder about this myself! ... I really don't know [how she would react if she found out]. It would really depend on what Liz tells her. David is the ultimate slime. I think she would be upset on all levels all around.

To play devil's advocate, now that we know she also had an affair, can she be so sanctimonious about it?
Pebdani:
I can see why you would say that, but she can do whatever she wants! [Laughs]

It's still not nice to be cheated on.
Pebdani:
No, it's not. It's like, oh, she was so young then, her husband was off to war. I don't even know if the affair happened when her husband was at war. But it's a different game when you're an adult. You're older now and you think you should know better. Maybe I'm just making excuses for her, but I think she has every right to be as absolutely hurt as she is.

Does Susan have any more secrets?
Pebdani:
There's got to be, right? And here we are in Shondaland - everything is possible. Every week, I show up in the writers' room, like, "Did I kill anybody?"

She hasn't killed anyone yet. Maybe she had Ronnie killed.
Pebdani:
Yeah, that would be really exciting. Hasn't happened yet, but the door is always open in Shondaland.

Scandal airs Thursdays at 9/8c on ABC.