Big Sky star Valerie Mahaffey on that mother of a twist

Warning: This article contains spoilers about Tuesday's episode of Big Sky, "I Fall to Pieces."

Big Sky might have just hit the mother lode when it comes to Ronald's propensity for evil.

On Tuesday's episode of the ABC drama, things came to a head between long-haul-trucker-turned-kidnapper Ronald (Brian Geraghty) and his repressive, overbearing mother, Helen (Valerie Mahaffey). Fully aware of her son's role in a sex-trafficking operation, Helen wrestled with trying to get him to do the right thing and prayed for his soul.

But when he admitted that he might resort to murder to keep his name away from the police, Helen's conscience won out. She confessed to Ronald that she had no choice but to turn him in. He snapped — and then so did her neck between his hands.

Much of Ronald's woe hinged on the fact that his former accomplice Officer Rick Legarski (John Carroll Lynch) had awakened from his coma, though he was a little lacking in short-term memory (and by short-term, we mean the last five or six years of his life).

As Jenny (Katheryn Winnick) and Cassie (Kylie Bunbury) continued to hunt for Ronald and leaned on the police to take action with Legarski, Ronald looked for a way out. Thinking it might lie with Merilee (Brooke Smith), he convinced her to let him come to her home (under the guise of the false name she knows him by). But as Jenny and Cassie showed up on her porch with a police sketch of him, could it be game over for Ronald?

To dig into Ronald's mommy issues and Helen's tragic fate, we called up the bad mom herself, Valerie Mahaffey (soon to be seen in French Exit), and discussed everything from how you film such a brutal scene to whether Helen might meet the same fate as Norman Bates' mother.

ENTERTAINMENT WEEKLY: You probably came in wondering if your days were numbered on this show given the setup, but when did you know this would be your fate?

VALERIE MAHAFFEY: I wasn't positive. [Series creator] David Kelley offered me the part pretty late into the process. Nobody told me at first that it was based on some books, C.J. Box's books. Helen is in those books, and what happens to her. [But] once I was already creating my version of Helen, I thought, "Okay, there's a book, but at this point I kind of don't want to know. I want to do my version." So I didn't know until a little bit later, but I suspected it was possible because David told me about how many episodes. But it went back and forth in my mind, which was cool, because the power struggle between her and Ronald, it seemed that she had that upper hand for a long time. I didn't know until the end that she was going to be able to to turn her son in. Because the love is warped, but it was very strong. And I didn't know if she was going to aid and abet him.

I don't think any of us watching knew either.

As an audience and as an actor, I like that. It's not a clear path in life either, is it? We vacillate on the right thing, the more expedient thing, the more whatever thing to do. And that's what Helen was going through toward the end.

Do you think Helen feared for her life or knew that this fate was a possibility by confronting Ronald?

I suppose so. Because in the last few episodes, he throttled her one time before and his power as a monster was building. The balance of power shifted, and so she was afraid of him. But she probably thought that she could pray for him and reason with him and do all the things that she had always done, and be able to express how much she loved him. And he would realize somehow in this epiphany that "Oh my gosh, Mom, you're right." I'm sure that that's what she really hoped for. She also was trying to stop a murder from happening. So she had to get her courage up to do that.

Why did she tell him she was going to call the police instead of just doing it?

She probably could have, but in the moment it was like, "No, don't go, please, come here. I love you, and this will be better for you." That's what it was. She was really hoping that he would see the error of his ways on his own. Instead of going out and betraying him without giving him a moment.

Ronald keeps blaming his mother for his insecurities and making him susceptible to Legarski's scheme. How responsible is she for the man he's become?

I think that there is responsibility to be had. We can't take all responsibility as parents, as mothers. I'm a mother, and I realize that it's a good thing that children ultimately rebel. But parents do have some responsibility, and Helen's agenda is just too strict. And warped, ultimately. You can't take a weak boy like that and tell him to go masturbate himself, how demeaning for him. In the beginning of the series, you saw him kowtowing to her and scared of her. Then he finally took his own [power] back, and it was just he was damaged by then. Badly. So it's not completely a parent's fault. I'm not going to take that on board. But I think we take some responsibility. In my life, I've known an awful lot of severely repressed people, and it comes out badly because they rebel overboard.

Ronald sobs over his mother, begging her to be all right, but ultimately he leaves her body there in front of the TV and goes on with his business. If we weren't convinced he's a sociopath before this, we should be now, right?

I don't know, was that the point? Well, he left the TV on for her. [Laughs]

What was the choreography like for your final scene? Did you have a fight choreographer or anything like that? It's so brutal.

I watched it last night. I knew what was coming, but that hand-to-hand combat version of death is really upsetting. I've died before in other things, but that was the most brutal. There was a choreographer there and a stunt double for me, but it definitely had to be planned out. It was odd when I was told how it was going to go down, and that I was going to have to die standing up. And then he was going to have to hold me by my neck, and I was going to have to not miss the chair that I ended up in. It was tricky. I'm determined for things to look real, so my dance training came in.

Will we see any more of you, whether it be Helen's corpse or in flashback? Is there a possibility Ronald is about to become Norman Bates 2.0 here?

I'm not telling you a damn thing. [Laughs] It's interesting — the comparison to Norman Bates' mom. That's been a strong [theme].

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