Shameless heroine Fiona Gallagher has hit the lowest of lows this season, leading to some bleak moments that gave her portrayer Emmy Rossum cause for concern.

“I was terrified that people would not like it and abandon the show because it’s so much darker than anything we’ve done before,” the actress tells TVLine. “We’re really changing the characters and giving them obstacles and making them fail. It feels almost like what they did on Breaking Bad, where they broke all the characters and made them really unlikable, and then started to redeem them again.”

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But first, you have to hit rock bottom, which is what Fiona did when she landed behind bars and found herself subjected to a strip search. The emotional scene — which earned Rossum the honor of TVLine’s Performer of the Week — was also traumatizing for the actress.

“That was a rough day [of filming],” she says. “That was one of the days where you go home and you go, ‘Wow, I hope that that was worth it because that definitely took a couple months off my life.'”

Below, Rossum talks about shooting that difficult moment and previews the troubling road ahead for Fiona, beginning with a visit from her probation officer (played by Southland‘s Regina King) in this Sunday’s episode (Showtime, 9/8c).

TVLINE | This season has been very brutal for Fiona. What has it been like for you playing her?

Honestly, this season was the hardest thing I’ve ever done in my whole career. That scene in the prison, during the strip search, I had a complete panic attack. I was completely naked when we did it. And it wasn’t like when I’ve been naked on set in the past where there’s been a sexuality to it, which for me is kind of easy because you’re just playing pretend. This was a nakedness with a complete removal of all your humility, your humanity. It was really scary for me to do that scene. Those feelings that came out were really, surprisingly, real for me.

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TVLINE | In the last episode, Fiona came to accept what she’d done and pleaded guilty, and she got this really grim description of her future. What is her state of mind now going forward?

She has some acceptance of her faults and her mistakes, but she’s about to realize what being a felon now means. Her life will never be the same. She can’t have the same jobs that she did. She’s no longer our golden girl who wanted to get her GED and wanted to set an example for the younger kids in this family. She’s fallen on hard times, and her family is really rejecting her in a way that is the most hurtful, even more so than being rejected from a job. You can always look for another job. She even goes to try to babysit for a woman she’s babysat for before and the woman says, “You have a drug problem now,” and Fiona says, “Well, you once dropped your kid at my house when you were up in Lawndale for a week, sticking a needle in your arm.” The woman’s like, “I’m sorry.” So she’s getting rejected on every level. She even goes to World Wide Cup to see if they’ll give her another chance, and Mike’s family basically eviscerates her. The low that she got and the fear that she felt in the prison, it was almost easier than being in the real world and dealing with the ramifications of the mistakes she’s made and the lack of opportunity that she will have now.

TVLINE | What does day-to-day life look like for her? She has that ankle bracelet, so she can’t leave the house, right?

She can’t leave the house at all, initially, and then she can only leave the house during certain hours where she has to find a job immediately. But the only jobs available are at night and she can’t work those because she has to be home at night. She definitely can’t get any kind of job like she might have had before in an office because she’s a convicted felon. So there’s a lot of new, awful, scary developments. At the same time, her family is out and about during the day. There’s only so many times you can clean the house and organize things before you go stir crazy.

TVLINE | One of the conditions of her pleading guilty was that she might have to serve jail time. Is that still a real possibility this season?

Only if she breaks parole.

TVLINE | How are the little kids, like Debbie and Carl, seeing her now? They’re much more impressionable.

They’re definitely happy that she’s home, but at the same time, she’s all over them because she wants so much to make up for her shortcomings and her mistakes. She’s trying too hard. It’s very obvious to the little kids. They’re like, “Listen, you messed up. Get away from me. We’re not the ones who were in jail.” It causes a big rift. Also, she’s finding it difficult to relax and accept her fate, accept her mistakes. She and Lip get into another really big row where he ends up taking the kids out of the house and taking them back to college with him. So she’s all alone in the house.

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TVLINE | Is Ian’s return a welcome relief for Fiona because he wasn’t there for all of this?

Yeah, although when he comes back, as we’ve seen in earlier episodes, he’s exhibiting really strange behavior. It almost seems like manic highs and lows of drug abuse. But what we’ll soon come to realize is that he has hints of bipolar Monica in him just like Fiona has been showing the qualities of Frank.

TVLINE | Fiona’s really been spiraling this season. Are we looking at a situation where it’s only going to get worse, or is she going to wake up to what’s going on with her?

I think it’s going to get worse before it gets better. The rejection she’s going to get from jobs and the rejection she’s going to feel from her family is going to make it really hard for her emotionally. She’s just going to want somebody to be kind to her, something to feel good, and sometimes that doesn’t come from the best place.

TVLINE | What does the season finale hold for Fiona and the rest of the Gallaghers?

I think it holds real hope in a way that I was really worried – and vocally worried in the writers’ room – that it wouldn’t. I was really terrified when I would get these scripts and it made Fiona so unlikable. I’m not afraid to be unlikable, but I’m afraid to be unlikable without having room to redeem myself. So I really feel that the Fiona we meet towards the end of the episode is gaining some maturity in the fact that she finally realizes she doesn’t have it all figured out. I think she needs to be in a program situation, an Al-Anon program, where she can really talk about her issues because they aren’t going away.