In “Supernatural” Season 12, episode 17, Dean (Jensen Ackles, pictured here) and Sam find the woman carrying Lucifer's (Mark Pellegrino) baby. The CW

The Winchesters are working with the British Men of Letters (BMOL). On Thursday’s episode of The CW’s “Supernatural,” Dean (Jensen Ackles) and Sam (Jared Padalecki) allowed Mick (Adam Fergus), a member of the supernatural-fighting organization, to join in their little werewolf hunt.

However, Claire Novak (Kathryn Love Newton) made an unexpected appearance and got bitten by a werewolf. Fortunately, Sam was able to save the young hunter from turning into a monster.

What will happen next week on “Supernatural”?

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The series ditches the case-of-the-week format and focuses on the main plot of Season 12. According to the synopsis of episode 17 on TVGuide, the boys get a major lead on Kelly Kline’s (Courtney Ford) whereabouts. The hunters and their angel friend Castiel (Misha Collins) have been searching for her for some time now. She is carrying Lucifer’s (Mark Pellegrino) baby and is protected by Dagon, the Prince of Hell.

Now, they have finally found Kelly. Unfortunately, Mick decides to drop by the bunker unannounced and join the hunt. Not good.

In fact, the BMOL feel the Winchesters are out of control and make their disdain known to Mick.

Things get worse between the hunters and the covert demon-fighting organization when a situation arises and Mick points a gun at them. “Mick you don’t have to do this,” Dean tells him in the promo. “Yes I do!” the BMOL member responds. It is entirely possible that Mick will be ordered to kill Kelly but the Winchesters and Cas want to find a way to protect her.

Suitably, this episode’s title is “The British Invasion.”

Meanwhile, Dean and Sam’s mother Mary (Samantha Smith) is still in bed, literally, with the Men of Letters. The trailer suggests that she is sleeping with someone. Is it a member of that shady organization?

“Supernatural” airs Thursdays at 8 p.m. EDT on The CW.