'Big Sky': Grace's Condition Is Getting Worse by the Minute in Tense Sneak Peek (Exclusive)

Jade Pettyjohn and Natalie Alyn Lind talk to ET about Tuesday's hour and say episode 5 features another shocking moment.

Is Grace going to make it?

Big Sky isn't afraid of pulling any punches when it comes to putting its characters through their paces, and on Tuesday's episode, it's no different. After unsuccessfully trying to flee from her hostage situation, Grace (Jade Pettyjohn) is in grave danger after getting shot in the leg twice by Big Sky state trooper Rick Legarski's (John Carroll Lynch) bow and arrow.  

In ET's exclusive clip, Legarski's partner-in-crime, Ronald (Brian Geraghty), tries to mend Grace's badly injured leg with hydrogen peroxide as Danielle (Natalie Alyn Lind) and Jerrie (Jesse James Keitel) look on in horror. When the first drop reaches Grace's open wounds, her screams of pain jolt the two other women into stunned shock.

"I know you want to help her, help us," Danielle pleads with Ronald. "You have a good heart, I can tell."

"Shut up! Next person who tells me what a good heart I have is dead, do you hear me?" Ronald threatens, before turning his attention to Grace, who is pale white, shivering from a fever, throwing up and worsening by the minute. 

"You can't leave her like this!" Danielle desperately yells, as Ronald picks up his medical kit and readies to leave the metal container they've been trapped in for days. "Where are you going?! You can't leave her like this! This is your fault! She's dying! You can't leave her!" 

"You’ll see in the next episode that it gets a little complicated when you're stuck with a wound, when you’re stuck in a trailer," Pettyjohn told ET's Leanne Aguilera about the aftermath of Grace's potentially fatal injury. The Little Fires Everywhere star also discussed the challenges of filming the heart-pumping chase scene from last week's episode. "It was such an incredible sequence to film. Our director, [Gwyneth Horder-Payton,] she was definitely a really important leader in that whole sequence because it's so physically tolling but also emotionally, staying in that headspace. Creating that as authentically as possible was just incredible. I was really lucky to have John Carroll Lynch and Gwyneth as a unit really create this space, as intense as it was."

Lind also spoke about creating the sisterly bond with Pettyjohn and whether Danielle steps up with Grace not at 100 percent. "In a way... Before we started filming, me and Jade had a conversation about how our relationship would be, and I really do feel like Danielle is comedic relief. She's extremely insensitive and selfish, if you haven't been able to tell," she shared. "She does continue down that path a little bit for longer. At the beginning of this, my entire goal for the end of the show and how I wanted her to be later on was to learn from the experience and not have it be something that happened to her. I really do think that's going to happen. I'm hoping she does step into more of a leadership position sometime soon."

As for the episode Pettyjohn and Lind are both excited for? Episode five, which airs next Tuesday. "Something happens in five [where you're] just like, 'Are you serious? Really?'" Lind teased. "That’s what I’m really excited for people to see."

Here's the official logline for this week's episode: "Unsatisfied with the investigation now that the girls’ disappearance has made headlines, Cassie and Jenny take things into their own hands, tapping into their individual strengths to make headway in the case. Meanwhile, Legarski attempts to keep cool, but Ronald takes a different approach to protecting himself. Still captive, Danielle and Jerrie tend to Grace, who makes a painful decision in an attempt to save them all."

Big Sky, which received an additional six-episode pickup on Monday, airs Tuesdays at 10 p.m. ET/PT on ABC. For more on the series, watch the video below.

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