Wynonna Earp star Melanie Scrofano previews 'sass rivalry' with Rachel Valdez

Wynonna Earp's Melanie Scrofano is very proud of Martina Ortiz-Luis's addition to the cast.

Ortiz-Luis made her debut as Rachel Valdez, the precocious daughter of deceased Black Badge Division scientist Gloria Valdez, in the death-defying fantasy horror show's season 4 premiere. Wynonna (Scrofano) and Nicole (Katherine Barrell) crossed passed (and fought zombies) with the snarky teen when they broke into an abandoned BBD building to find an entrance into the Garden. Interestingly, Scrofano had a hand in casting Ortiz-Luis because she directed episode 3, which was the first thing they shot when production began.

"It's such a new energy to have on the show. I get real cocky every time she comes on-screen because I’m like, 'Yeah, that’s my baby.' I adore her," the titular hero's portrayer tells EW. "It’s sort of nice because Rachel gets to be the audience, in the sense of just taking in these people as fresh eyes and being like, 'You guys are weird.' That’s a fun angle to play. Wynonna has a huge heart but takes a minute to get into it. I think it’ll be an interesting sass rivalry going on."

Wynonna and Rachel's prickly dynamic is on full display in the above exclusive sneak peek from the season's second episode "Friends in Low Places," which airs Sunday night. Picking up after Nicole's plunge, the clip shows the duo matching wits as they avoid the walking dead and search for another route to the lower level, where they hope to find Nicole, Rachel's mother, and the gate to the Garden. To Wynonna's surprise, Rachel is rather pragmatic about what she'll do once she finds out if her mother is dead or zombie.

"Rachel, there’s so much in her life that she plays it quite cool, whereas Wynonna has no cool. She has no chill. Again, it’s just an interesting pairing. I love Rachel and Martina," says Scrofano."This is one of the reasons why I loved her when I saw her audition. She looks like somebody you would need to take care of. She looks like somebody [where] your instinct would be, 'I need to protect this girl. She’s so young,' and then she says stuff like that and you’re like, 'Eh…can you protect me?' I think because of what she’s been through and the conditions she was living under by herself, I think her reality became a lot harsher a lot earlier and in a lot of ways forced her to mature and deal with things in ways that most kids don’t have to."

The promo for episode 2 also teases that Wynonna will reach the Garden and find Waverly (Dominique Provost-Chalkley); however, according to Scrofano, that's only half the battle.

"The thing about the Garden is that it will change the dynamic [between the sisters], especially in that episode. I think Wynonna and Waverly have a lot in common but only Wynonna has been through it and can speak more clearly to what Waverly is going through. There’s definitely a fight for Waverly beyond whatever is holding her there. It’s like a fight for her mental state, too, and a fight for her to come back," says Scrofano.

Watch the clip above.

Wynonna Earp airs Sundays at 10 p.m. on Syfy.

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