Agents of SHIELD's Jemma Simmons has changed, both for the worse and the better.

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The scientist spent six months alone on an alien planet, and while it will be some time before her intergalactic adventures are revealed, viewers can expect to see a different side to Simmons (Elizabeth Henstridge) in the meantime.

"She's definitely still her essence - she doesn't just completely change," Henstridge teased, according to Entertainment Weekly. That's not to say longtime fans won't be able to pick up on a difference.

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In fact, we've already had a glimpse of the agent's nightmares. Luckily for Simmons, what doesn't kill you makes you stronger.

 "She's been through so much. She's hardened," Henstridge explained. "She's had to face things that she never would've imagined, also by herself without Fitz [Iain de Caestecker], so she's definitely changed, stronger and kind of damaged."

So how long will it be before Simmons is back in the lab? Henstridge couldn't say, but from the sound of it, it won't be too long. If Andrew Gardner gets involved, however, there's a chance Simmons will be treated to the same "observation" routine Daisy's Inhumans are currently experiencing.

Find out more when Agents of SHIELD airs Tuesdays at 9 p.m. ET. On ABC.