Supernatural's Sheriff Mills will be taking on a nest of vamps during "Alex Annie Alexis Ann," and her protective instincts will kick into high gear when a human's life hangs in the balance.

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The Sioux Falls sheriff will make an unexpected discovery when she ganks a local bloodsucker - a captive human that the nest has been using to lure in humans. Unfortunately, Annie (Katherine Ramdeen) will have a slight case of vampiric Stockholm syndrome and the former blood slave will do anything to keep her "family" safe.

While Mills (Kim Rhodes) has battled everything from the King of Hell (Mark Sheppard) to her own zombie son, this mission may prove to be too much for the dedicated cop. Could Mills' ninth Supernatural appearance be her last?

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"I'm in next week's #spn," Rhodes tweeted on Tuesday. "I won't live-tweet, I'll cover my eyes and you can tell me how it ends. #amidead."

As fans cross their fingers and toes in the hopes that the CW series won't kill off the fierce hunter, writer Robert Berens promises that the episode will definitely do Rhodes' character justice.

"I'm reluctant to say anything about the ep[isode] but telling you all that @kimrhodes4real will knock your socks off is #nospoiler," tweeted Berens during filming back in March.

Scroll through the photos above and click the sneak peek below to get a taste of what's to come in "Alex Annie Alexis Ann."

Supernatural airs Tuesdays at 9 p.m. ET on The CW.