WARNING: The following contains spoilers for Big Sky Season 1, Episode 5, "A Good Day to Die," now available on ABC.

ABC's Big Sky hasn't shied away from shocking final scenes, especially since the premiere killed off the man viewers thought was going to be the lead. Instead, it's fallen to his two exes and former colleagues, Cassie and Jenny, to solve the case of the missing girls down in Montana, which has unsurprisingly found them breaking laws.

The midseason finale takes a surprising turn, though, when another brutal shooting occurs. However, this time, the show murders a major villain in the vein of The Departed, changing the complexion of the entire series.

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Sisters, Danielle and the wounded Grace, and the transgender Jerrie are still being held by Rick, a state trooper, and Ron, a demented and lonely trucker, with the men desperate to ship them off to Canada as the heat's coming down. Danielle's dating Jenny's son, so the P.I.'s won't stop until they know who abducted the girls and why Cody's missing. This led to Cassie planting a GPS on Rick's car, but their raid with Sheriff Tubb came to naught.

Ron's already taken the girls away and stored them at Rick's bar, with evidence now pointing to Cassie and Jenny being way too emotional and irrational. It gets heated as Rick's superiors arrest Jenny for illegally tracking Rick and endangering his life, but Cassie takes this as an opportunity to peer deeper into his mind.

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Cassie tries to shake Rick's estranged wife, Merilee, and get info, but she's also in the dark. She remembers something, though, about serial killers going back to their hotspots, due to their ego and slips away to the bar. There, as Ron's back home sorting out his own issues with his mom, Cassie sneaks in just as Rick's prepping the ladies for buyers. Grace is badly damaged, while Jerrie and Danielle are too small to overpower the giant, but Cassie's got an equalizer in her gun, meeting Rick at the top of the basement stairs.

He's at the bottom, joking about holding the girls as hostages, trying to intimidate Cassie into thinking she's trespassing. But when he sees her hands shaking, he calls her out. Rick's playing mind games, but before he can grab his gun, the final shot of the episode has Cassie pulling the trigger and putting a bullet through his forehead in a graphic sequence.

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It happens in the blink of an eye, reminding viewers of when Martin Scorsese killed off cops in the finale of The Departed, starting with Leonardo Dicaprio's Billy Costigan. Trooper Barrigan shot him through the head in the elevator, before murdering Trooper Brown. Matt Damon's Colin Sullivan would then do the same to Barrigan before Mark Wahlberg's Dignam finishes the headshot parade by sniping Colin.

With Rick's lifeless body on the ground in Big Sky, it seems like a victory for the ladies. However, writer Jonathan Shapiro has indicated Cassie could face legal repercussions. Additionally, while she can take gratification knowing she killed a racist and misogynist, Cassie still has no clue what Rick did with Cody's body.

Big Sky stars Katheryn Winnick, Ryan Phillippe, Kylie Bunbury, Brian Geraghty and Valerie Mahaffey. It will resume Tuesday Jan. 26 at 10 p.m. ET on ABC.

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