If someone were to tell Sam (Jared Padalecki) and Dean (Jensen Ackles) in Season 10 of Supernatural that Crowley's (Mark Sheppard) witch of a mother Rowena (Ruth Connell) would eventually become a trusted ally, they probably would have broken out the Rituale Romanum and staged one hell of an exorcism.

However, in Season 14, which finds Rowena closer to redemption than ever before, the improbable notion of her fighting on the side of good is now a reality. That's not to say the delectably devious sorceress doesn't still have a few tricks up her sleeve, but now that she's allowed herself to find her conscience and develop a genuine affection for the demon-hunting brothers, it's safe to say she's no longer the villain of their story.

Discover your new favorite show: Watch This Now!

The reformed baddie brings her irresistible charms to this week's Supernatural as Sam and Dean take on a flesh-eating demi-god who remains one step ahead of them. But the real fight might come from one of their own: Jack (Alexander Calvert) is spiraling as he continues burning off his soul to help the team, a risky move that has Castiel (Misha Collins) and the rest of the crew concerned. It's especially alarming for Rowena, who left Jack on the brink of death several weeks back only to find him very much alive.

"Rowena's freaking out at the fact that last time she saw Jack he was on death's door, and now he's kind of back to normal, but she's unsure. Why is he okay?" Ruth Connell told TV Guide.

The upcoming episode, titled "Ouroboros," will see Jack and Rowena at odds. Their inevitable standoff is complicated by Rowena's special bond with the Winchesters, as well as by the fact that Cas, Sam, and Dean's adoptive son has also gotten under her skin. "In many ways, I'm Jack's Auntie Rowena," Connell said. "I think Rowena has a soft spot for Jack."

Subscribe: Apple Podcasts/Stitcher/Google Play/iHeartRadio/TuneIn

With Rowena on the path toward redemption, which Connell teased we'll see more of this week, how she handles the Jack problem may prove essential to the direction that her story takes next.

The episode will also feature plenty of twists and turns elsewhere, with the imminent threat of Michael still looming. Things are bad — really bad — for Dean right now. He's barely sleeping from Michael's constant pounding in his head as the archangel desperately fights for a way out. Dean may soon find himself on the losing end of his toughest battle to date. It's a struggle that affects everyone around him, including Rowena, who now feels most at home with Cas.

"He's the most normal one, which is saying something," Connell said.

Supernatural returns Thursday, March 7 at 8/7c on the CW.

(Disclosure: TV Guide is owned by CBS Interactive, a division of CBS Corporation.)

PHOTOS: These Are the 100 Best Shows Right Now

Ruth Connell, <em>Supernatural</em>Ruth Connell, Supernatural