‘Supergirl’ Spoilers: Melissa Benoist, Katie McGrath, David Harewood Tease Battle Against Reign

“Supergirl” stars think that fans will be shocked by how powerful Reign is.

In a recent interview with TVLine, Melissa Benoist said that Sam’s (Odette Annable) evil alter ego is going to surprise people. “Reign is pretty spectacular to behold, and she will give Supergirl the fight of her life,” Benoist, who plays the titular character on the CW series, told the news outlet. “What sets her aside from the Big Bads that we’ve seen up to this point on the show [is that] she has a really surprising back story that gets you really invested in who she really is fundamentally.”

David Harewood added that Reign will become a lot stronger than anyone expected. “She’s full of surprises,” the J’onn J’onzz portrayer said of the Season 3 Big Bad. “I’ll put it this way: I walked on set the other day and was shocked at what I saw. It’s a pretty arresting sight. Reign doesn’t exactly treat people with kid gloves.”

Given Reign’s Kryptonian heritage, some fans may have assumed that she has the same abilities as Supergirl and her cousin Superman (Tyler Hoechlin). But former executive producer Andrew Kreisberg revealed to Comic Book Resources that viewers “will definitely see some surprises” in that matter. “Hopefully, it’s not straight up what people are expecting, as always. We’ve got a couple of really nice twists and turns,” he teased.

While fans have yet to see Reign’s capabilities as a World Killer, Kreisberg previously told TVLine that Reign “will be more than a physical match for Supergirl.”

Although Benoist noted that Kara “will always choose to fight to change someone’s mind or to make someone see the good in the world,” bringing Reign to the good side might be impossible.

Going against Reign will obviously be difficult for Kara, but the situation will also be hard for Lena (Katie McGrath), who may not only lose her company’s CFO but may also lose someone she now considers to be a close friend. “You see how close Kara, Sam and Lena are getting, I can’t imagine that it isn’t going to become difficult with Sam essentially being Supergirl’s arch-enemy and all three of us being friends,” McGrath said. “It’s got to come to a head somehow.”

Unfortunately, Sam’s transformation into Reign will divide Team Supergirl. “Some will believe she needs to be saved; others will think she needs to be stopped,” Kreisberg told TV Insider last September.

Watch the Girl of Steel go head-to-head with Reign for the first time in Season 3, episode 9 of “Supergirl,” airing Monday, Dec. 4 at 8 p.m. EST on The CW.