Brianna Hildebrand is undeniably badass in Deadpool as Negasonic Teenage Warhead, an apathetic, gothic mutant with the power to detonate and peer into the future.

ET chatted with the 19-year-old actress about her experience on set, becoming an X-Men apprentice, and her teen crush on Ryan Reynolds.

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"I actually had photoshopped myself into a picture with him when I was maybe a freshman in high school," laughed Hildebrand, who eventually showed Reynolds the photo on set. "I'm like, ‘Ryan, look at this! You used to be my best friend in my mind!' He did a great job of not seeming super freaked out."

In fact, Reynolds and the rest of the Deadpool cast were quite supportive of Hildebrand, who is relatively new to the acting universe.

“I was pretty nervous coming to set because everyone was so much more experienced than I was,” said Hildebrand. “I had a talk with almost everyone in the cast and they just really reassured me that I was in the right place and that I knew what I was doing.”

WATCH: Hugh Jackman Teases Possible ‘Deadpool’ Showdown 

Deadpool hits theaters on Feb. 12, and there are already talk of a sequel – plus, the burning question of whether crossovers with the X-Men might happen in the future.

“It would be cool if [Negasonic Teenage Warhead] could hang out in the X-Men world a little more,” said Hildebrand, who would like to have some scenes with young Storm. “I know Alexandra Shipp personally and that would be really cool to work with her.”