'Supernatural': Lily Sunder Is Out for Revenge...and Castiel Is in Her Crosshairs

Marisa Roffman
Diyah Pera/The CW/© 2017 The CW Network, LLC. All Rights Reserved

Pictured (L-R): Alicia Witt as Lily, Misha Collins as Castiel, Jared Padalecki as Sam and Jensen Ackles as Dean

A blast from Castiel's (Misha Collins) past returns in this week's episode of Supernatural…and it's a scramble for Sam (Jared Padalecki) and Dean (Jensen Ackles) to save the angel's life.

Lily Sunder (Alicia Witt) has spent the past century looking to get revenge against the angels who killed her family—with a dash of black magic on her side—and now she's set her sights on Castiel. "It's not necessarily a positive history," Witt downplayed to reporters on the show's Vancouver set, acknowledging the role required a lot of fighting. "There's perhaps a bit of friction there."

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With Castiel's friends being taken out one by one, "we are dealing with some of Cas's old battalion mates from heaven," Collins said. "I think it's interesting for him to rehash hold memories, for sure."

The hour, "Lily Sunder Has Some Regrets," gives viewers a chance to see what Cas was like before.  "Before he was humanized a little bit," Padalecki reveals. In fact, "we're seeing the earliest version of Cas to date," Collins said. "Which is kind of interesting to say the least."

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As for Lily, Witt—who has been a part of a high-profile, top-secret projects in recent years (including the Twin Peaks revival and The Walking Dead)—wasn't fully looped in to her character's secrets before she landed the role. "When I auditioned for this, they told me very little about my character, similar to my experience auditioning for The Walking Dead," Witt recalled. "A lot of specifics were cut out of my audition scenes; the audition scene was a bit of a composite of a couple different scenes, but it was all very nebulous. Just like the scene with The Walking Dead, it didn't quite make sense, but I knew what the title of the episode was, so I was like, 'I bet you I have some pretty juicy stuff to do.'"

The hour also marked a mini-reunion for Ackles and Witt, who appeared in a 1997 episode of Cybill together. (Witt was a series regular on the CBS comedy.) "Oddly enough, I like don't even remember that experience," Ackles said. "Looking at it, I'm like, 'Yup, that's me.' But I was so young and wide-eyed. 'Just shut up, don't get in the way, know your lines, hit your mark and keep your mouth shut.'"

Ackles reminded Witt of their history when she landed the guest spot, and she found the footage of them together. "We were both so young," Witt marveled. "Somebody had compiled a YouTube video of his scenes on the show and there was me right there with him!"

Supernatural, Thursdays, 8/7c, The CW