Paget Brewster, Thomas Gibson

"People everywhere were coming up [to me] and saying, 'Why did you die?'" Criminal Minds star Paget Brewster told the audience at Tuesday's Paley Center fall TV preview, which was moderated by TV Guide Magazine's Michael Schneider. "Fans did not want their show being messed with."

CBS' popular crime drama "messed with" Brewster's character Emily Prentiss last season when they wrote her off the show by faking her death within the FBI's Behavioral Analysis Unit (BAU). After leaving the series, Brewster shot another pilot, which ultimately did not get picked up, leaving her free to return to Criminal Minds. She credits fans worldwide with getting Prentiss back on the show for Season 7, which premieres on Wednesday, Sept. 21 at 9/8c.

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"I know 'muerte,'" said Brewster. "I now know 'death' in several languages. People in airports in Mexico would come up [to me to ask about Prentiss' death]. I'm like, 'I know. Lo siento!' The fan response was overwhelming for everyone I think."

Prentiss' BAU resurrection will be a pivotal part of the changes coming to Criminal Minds. Check out what else the cast and crew revealed about what to expect in Season 7:

1. Expect a different BAU. "It's a season where we get to explore our heroes a little bit more," showrunner Erica Messer said. "Every week we get to dive into what makes these bad guys tick, and this is the season where we want to explore all the layers that make up this team. We get started right away with Prentiss returning from the dead. ... This event has changed all of our characters' lives."

2. Things get hairy for Hotch. The Paley Center played a preview clip showing Unit Chief Aaron "Hotch" Hotchner (Thomas Gibson) sporting a full beard, at least temporarily, while he's out of the country. "Hotch, as you saw, was in Pakistan," confirmed Messer. "That was mainly because I saw this handsome devil with a beard and said, 'Can you keep that thing? We should write to it.'"

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3. Morgan tracks down Prentiss' killer. "Morgan made it his life journey to get redemption for his friend," Shemar Moore said about his character, Special Supervisory Agent Derek Morgan. Messer added, "No matter what, he wasn't going to let Ian Doyle (Timothy V. Murphy) be out there in the world. ... Morgan's been looking for him. He did it in the traditional way that profilers do, by getting into the head of the bad guy. He realized that the whole thing that's keeping Ian Doyle going is that his son is still out there. Morgan and Garcia (Kirsten Vangsness) begin digging around: Where would Doyle's son be? Where would Prentiss, our friend, have hidden him? So they're [also] profiling Prentiss."

4. Hotch + Morgan = Splitsville? Moore said, "There was a sense of betrayal from Hotch, even though that's his friend, that's his boss." Gibson added, "I think the theme of broken trust within a family will have a chance to play in various ways and various times in this season and maybe beyond."

5. JJ got a promotion. A.J. Cook's character Jennifer "JJ" Jareau was also written off the series, but was brought back after fan outcry. Not only was she part of the conspiracy hiding Prentiss' faked death, but she's also been busy with new duties. "JJ's been back for three-and-a-half months," said Messer. "She's been promoted to a profiler in that time. And we hear a little bit more about that in Episode 2."

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6. Garcia will control the remote. Since JJ's now profiling, she won't introduce the cases. That duty falls to tech analyst Penelope Garcia, whom Vangsness said will be in the field, "at least in the round table room, at least holding that remote, explaining some stuff, which she does not enjoy doing. She likes being with them, but she does not enjoy the violence, so there's a lot of 'Here's the thing' [and] look away."

7. Dr. Reid will have family problems. "Reid had been dealing with his mom, which might have been something we lost in the premiere, but we touch on in Episode 2," Messer said. Matthew Gray Gubler, who wore two different socks (one pink, one blue-and-black striped) at the Paley Center event, couldn't reveal if his nerdy character's headaches would be addressed or if Reid would be getting a girlfriend. "I don't know, man," he said. "I'm always the last to know."

8. Rossi's first ex-wife could linger. As previously reported, Senior Supervisory Special Agent David Rossi (Joe Mantegna) will have to deal with his first ex-wife (Isabella Hoffman) when she comes to him for help. "It's kind of a two-part thing," said Mantegna. "We've established over the last few years that Rossi wasn't great at marriage. ... I thought if he were married three times to at least address a portion of that."

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9. Ian Doyle will be back, briefly. "We see a wee bit of Ian Doyle [in Season 7]," Messer confirmed. "We're thinking that maybe [we should write that] he has an evil twin brother because [Murphy is] so great."