Julian (Tom Felton) awakens Frankie’s (Joey King) dangerous alter ego in a sneak peek for Season 3, episode 3 of “The Flash.”

In the two-minute clip, Julian finds out that Frankie is a metahuman after learning that her DNA has the same element he discovered in the five husks the police recovered around Central City. After confirming his theory, Julian — with Barry (Grant Gustin) in tow — rushes to the police main headquarters just below their laboratory to stop Frankie from leaving the station.

“You’re a metahuman,” Julian yells at Frankie who is about to get out of the building. “You put your foster father in the hospital, didn’t you? Didn’t you!?”

Unfortunately for Julian, confronting Frankie puts him in a precarious situation as the claims he made about her force her metahuman identity, Magenta, to emerge. “Oh I wanna do more than hurt him,” Frankie says of her foster father. “Now, I’m gonna do the same thing to you.”

As revealed by Comicbook.com last August, Frances “Frankie” Kane is a teen with a troubled past. Like the famous “X-Men” villain Magneto, Frankie has the ability to control all things metal. The use of her power, however, comes with a perilous consequence, causing her villainous alter ego to surface from within her.

In the same episode, Earth-2 Wells (Tom Cavanagh) and his daughter Jesse (Violett Beane) will return to Earth-1 with exciting news. According to the synopsis of the episode, Wells reveals to Barry and Caitlin (Danielle Panabaker) that Jesse is now a speedster and has been saving people on their Earth. However, he is worried about her safety and wants them to mentor her in using her super speed.

“The Flash” Season 3, episode 3, titled “Magenta,” airs on Tuesday, Oct. 18 at 8 p.m. ET on The CW.

Tom Felton Julian (Tom Felton) figures out that Frankie (Joey King), a.k.a. Magenta, is a metahuman in a sneak peek for Season 3, episode 3 of “The Flash.” Pictured: Felton poses on the red carpet for the film “A United Kingdom” during the opening night gala event for the BFI London Film Festival in London on Oct. 5, 2016. Photo: DANIEL LEAL-OLIVAS/AFP/Getty Images