'Tomorrow People': Alexa Vega Previews 'Ruthless' Debut

Tomorrow People Alexa Vega Robbie Amell Rumble Still - H 2014
Katie Yu/The CW

The Tomorrow People welcomes a new foil, who gives Stephen (Robbie Amell) a run for his money.

In Wednesday's episode of The CW drama, Spy Kids alum Alexa Vega makes her debut as Hilary, an Ultra agent whom the actress describes as "ruthless" -- even going so far as to say, "she's Hermione Granger and Draco Malfoy put together."

"Hillary is brutally competitive and is the type of girl who stops at nothing to get to the top and she doesn't play nice," Vega tells The Hollywood Reporter. "She's cutthroat. If something is in her way, she's going to do everything to remove that obstacle -- whatever that may be."

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When Hillary gets introduced to the Tomorrow People universe, she and Stephen are placed in a competitive setting -- one that puts every person of their ilk in danger of becoming mortal.

"What's going on at Ultra is the agents in training are having this competition. Jedikiah (Mark Pellegrino) says that if you're a weak link in Ultra, you'll be stripped of your powers because you're not worthy of it," Vegas says. "That really puts the teamwork at risk and we're all fighting against each other now."

Stephen's familial ties to Jedikiah becomes a point of contention for Hillary. "Because Hillary knows Stephen is Jedikiah's nephew, that's really frustrating [for her] because she feels he has a leg up on her already," Vega explains. "She really picks on him and fights him and does a lot of following to spot his weaknesses."

That "research" leads Hillary to an unexpected place by the end of the episode. "She follows Stephen and sees both him and Astrid doing something Stephen shouldn't be doing," Vega says, hinting that the intel becomes crucial. "It'll be interesting to see how she's going to use this against him in upcoming episodes."

Whether Vega's character will interact with other characters in the Tomorrow People universe outside of Ultra remains to be seen; currently, she's an Ultra loyalist.

"Her main thing is survival. She's not worried about anything else. She's just worried about keeping her powers and becoming a top Ultra agent because she knows she'll be able to survive that," says the actress, revealing that her interactions are mainly with Stephen and Jedikiah.

Vega hints that she will begin to explore further into Stephen's life, including the people he interacts with, like John (Luke Mitchell). "Everybody should be prepared for Hillary," she teases.

Watch a preview below.

The Tomorrow People airs Wednesdays at 9 p.m. on The CW.

Email: Philiana.Ng@THR.com
Twitter: @insidethetube