9-1-1 fans, are you still catching your breath?

Thursday’s episode was one of the more intense installments of the ABC first responder drama, with Maddie (Jennifer Love Hewitt) held captive in a basement by Det. Amber Braeburn (Timeless, Suits, and Mad Men alum Abigail Spencer). The kidnapping culminated with Braeburn attacking Chimney (Kenneth Choi) and ultimately shot dead by Athena (Angela Bassett) — but not before exposing the missing persons detective’s multiple personalities and painful past.

Reflecting on the emotional (but also laugh-filled) filming of their basement scenes, Hewitt and Spencer tell Entertainment Weekly about handling the emotion and physicality of the material, not knowing the biggest twists and turns when shooting started, and how they envision Braeburn could pop up again in the future.

ENTERTAINMENT WEEKLY: This isn’t the first time Maddie gets kidnapped on 9-1-1…

JENNIFER LOVE HEWITT: What’s different this time is I think you never believed for one second that she was going to stop fighting — and her anger was stronger. Her frustration about not being able to get herself out of there was stronger. It was nice to be able to see her use her dispatcher side to kind of get into the mind and the heart of these multiple people that she was dealing with.

ABIGAIL SPENCER: Sometimes I would forget my lines because I’d just be watching her. She’s so tremendous. I was like, “Did you just make your tears do backflips? How do you do that?” I looked at Angela, and I was like, “Can you do that?!” And she’s like, “Girl, no.”

Jennifer previously told EW you didn’t have the full script when you started filming. Abigail, how did you handle the twists and turns as you got new pages?

SPENCER: I’d get my nine pages of dialogue, and I’m like, “Oh, okay….” I kind of looked at it as performance art. I was like, “What’s going to happen today?” Jennifer knew more than I did, as she should, but also this show is very alive. They’re definitely constantly shifting and changing directions if they see something is working. So I knew there was a twist, but not to the degree…. Jennifer was like, “Yeah, we’re going to be trapped in a basement for a week.” And I was like, “I’m sorry, what?” And she’s like, “Yeah, we get into a fight.”

HEWITT: It was crazy. I mean, when I say that Abigail and [director] Jen Lynch and I really had to make a pact of like, “Okay, we’re going to go for this, and everybody’s going to keep each other safe, and it’s all going to be with love and light, but let’s go for the darkest part that we can get.” We did that and it was good and fun to do because we all trusted each other. I knew that if at any moment I needed anything or I got too much, Abigail and Jen would have me, and they knew the same about me, and it was beautiful to have three women get together and do that. It was a real experience that I will never forget.

SPENCER: It was very, very intense for days, for days on end. But we were also laughing. We were just dying laughing between takes, and then she’d be doing back flips with her tears. Meanwhile, I’m like, “Which personality is going to show up today?”

How did you decide to approach Braeburn’s multiple personalities?

SPENCER: Multiple personality disorder is real. So, at the end of the day, it can be the sensational story, but it is real — and for this character, this is real. This is really happening and these horrible things are happening and that this person doesn’t want to be happening. So I think it’s a dance.

HEWITT: Watching Abigail navigate every person at any given moment, and sort of find the differences between them, was very special to watch in person. I think that Abigail did a beautiful job of showing that and showing not just nastiness and terror and horrible human the whole time, but really nuances of hurting people all in one body. The thing that I love about 9-1-1 and what [co-creator and showrunner Tim Minear] does is…. Even in [Maddie’s ex-husband] Doug, even in all of the characters that Abigail plays in these episodes, every truly bad person or person that it’s hard to find any sort of redeeming quality in, he adds in this pain and this inner turmoil and hurting in them that somehow makes you connect to them.

Where does Maddie go from here now that she’s escaped?

HEWITT: Maddie is the ultimate survivor and fighter, but I think this one stays with her. If you compare this to leaving Doug and Big Bear the way that she did…. That was a cleansing. That was a letting go and starting over. This is different, because it’s so complicated. I really think Maddie hoped and thought this pregnancy would not have trauma involved, and it does. I think that the call centers being the innocent, pure place for her — where she can run when the world gets really scary and it’s always safe for her — that has now also been damaged. I don’t think it will be a super long thing, but she’s got some stuff to go inside and pick back up.

And what about Braeburn? 9-1-1 finds ways to bring back dead characters…

SPENCER: Well, Kenny Choi was like, “Maybe there’s a Ghost of Braeburn spinoff.” One of the crew guys was like, “Maybe Det. Braeburn comes back and haunts Maddie.” I mean, look, you can do anything on 9-1-1. It’s genre bending.

HEWITT: I do think that Braeburn comes back as a ghost. Maybe you don’t physically see her, but I think she has gotten under Maddie’s skin in a totally unique and different way, and Maddie will continue to have to survive that.

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9-1-1 airs Thursdays at 8 p.m. ET on ABC.