Agents of SHIELD's Jemma Simmons is back...and she's brought a whole host of new problems with her.

'The Librarians' Season 2: This Year's Big Bad Revealed, Who Will Cause Chaos This Winter?

After a harrowing few moments and a true SHIELD team effort, Simmons (Elizabeth Henstridge) found herself safely back on earth as "Purpose in the Machine" came to a close. Months stranded on a hostile alien planet, however, will leave the scientist changed in more ways than one.

From Simmons' PTSD to a possible galaxy-jumping enemy, the world of SHIELD just become slightly more complicated.

'Grimm' Season 5 Spoilers: Two New Episode Titles Revealed, 'Destruction' In Store?

"Now that she's back, it's not like, 'I'm fine, moving on!'" Henstridge told Entertainment Weekly. "It will have a huge impact on the rest of the season. Psychologically, she's petrified that she's not safe."

But what is she scared of, exactly? Hesntridge couldn't say, but viewers will certainly find out as the season moves forward.

"She's completely at zero, so it's going to take a second," Henstridge teased, explaining that it will be some time before Simmons returns to work. "She's really struggling. We'll definitely find out why she's struggling so much in later episodes."

What do you think Simmons encountered during her abroad? Sound off in the comments below!

Agents of SHIELD airs Tuesdays at 9 p.m. ET on ABC.

Tags: Marvel's Agents of S.H.I.E.L.D. television ABC Marvel