'Big Sky' Winter Finale: Legarski Vows to Put a Stop to Cassie and Jenny in Chilling Sneak Peek (Exclusive)

The clock is ticking.

Time is not on Jenny and Cassie's side.

After narrowly missing the kidnapped girls in the secluded cabin by mere inches, the estranged friends are at the top of Ronald and Legarski's hit list on Tuesday's winter finale of Big Sky. Ominously titled "A Good Day to Die," the episode sees Jenny and Cassie getting closer and closer to the truth behind Legarski's sinister ways, but the small-town state trooper has other plans to stay a step ahead.

In ET's exclusive sneak peek, red flags fly for Ronald (Brian Geraghty) and Legarski (John Carroll Lynch) when they realize that the tread marks on the mud aren't from a random passerby who got lost, but someone who came looking for something -- or rather, someone.

When Legarski gets increasingly agitated that their plan may be foiled by Jenny and Cassie digging around for the truth, he and Ronald bicker over who slipped. 

"The walls are closing in because you took those teenagers!" Legarski threatens Ronald.

"Or maybe because you killed a cop!" Ronald fires back, referencing Cody's cold-blooded death.

OK, so they both let go of the leash a little bit. Legarski reveals their next plan of action: They need to "get rid of these girls" so Jenny and Cassie won't find them. But first, it's time to take care of another larger problem: Cassie and Jenny.

"Cassie Dewell and Jenny Hoyt," Legarski says. "I work with this police dog, a bloodhound, she can track anything. She'd pick up a scent. Relentless. They remind me of that dog. They're not gonna quit... which means they need to be stopped." 

Uh-oh, should we be worried about Cassie and Jenny?

The winter finale of Big Sky airs Tuesday at 10 p.m. ET/PT on ABC. For more on the series, watch the video below.

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