Emily Deschanel and David Boreanaz in BONESBones" about it: saying goodbye to her TV series after 12 seasons was a mixed bag of big emotions.

With the series finale of the enduring forensic crime procedural looming ahead on March 28, the actress admits that she's already run through a gamut of feelings as she, co-star David Boreanaz, and the rest of the cast and production team bring the saga of Brennan and Booth to a conclusion -- and she expects even more emotional fallout when audiences finally take in that very last episode.

Deschanel, who's perhaps more keyed into her emotions than the pragmatic and empirical-minded Brennan, recently joined a small group of press to reveal her many moods about closing out "Bones."

Did you know any of [series creator] Hart Hanson's original plans for the ending, even with the new showrunners coming on board after he left?

Emily Deschanel: No. No, I didn't. You mean like what plans he had? No, I don't. Nope. He didn't tell us that kind of stuff ... I asked them, "Had you talked to Hart about things?" And they said yes. They said, whatever they could do what Hart suggested and wanted, they would.

But a lot of the storylines had already been used in the show after Hart had left because we have so many episodes, and we had a lot of episodes that were supposed to maybe possibly be the finale, so we kind of had false endings sometimes.

Is that strange for you to have an ending that became not-an-ending several times?

I got used to it at a certain point. We never ended [a season] thinking, "This is the end." We ended it thinking, "This could be the end," so we had to end it finally in a way that feels like an end, but also have a possibility of doing the show later.

So we never thought, "We're done." We thought, "We don't know." [When] you're on a television show, especially like this one, you always are in limbo, and you never know that the future is in terms of at least the next season. Usually they picked this up for a full season when they did.

You've gotten 12 years to play this character, which is really rare.Tell me what that means to you to have taken her from point A to point Z over that period of time and play one character in all those different ways.

Yes. It's amazing. Such a gift. It's such a treat as an actor. When you do a movie, you only have an hour and a half, two hours to tell a person's story. And to grow and change, I think to do that over time in this way where it's kind of gradual, like life. You're really living with these characters over all this time. It feels like it becomes a part of you in a lot of ways.

And it's such a treat to grow with a character and get to feel the character change, and put the character in different scenarios, and relationships to change with the character. It's such a real treat as an actor that's obviously incredibly rare.

Is there a piece of medical jargon that you can never un-know?

Epiphyseal fusion ... I don't know! There's so many different things, terms ... ways to tell how old the dead body is. How old somebody is, what race they are, things like that. My rule is always that I have to know what I'm saying when I say it, but I don't have to remember it the next day. But certain things stick.

Brennan was one of TV's leading female characters in STEM [Science, Technology, Engineering, and Mathematics]. What does it feel like to be part of that early wave of these characters? Now we have networks going out specifically looking for scripts with women in STEM roles.

I didn't know that, but that makes me incredibly proud. That's one of the main things that drew me to the part. When you choose a character to play, when you choose a project, when it's a television series, it's just a pilot. It could end after the pilot. But you also have to think of the possibility that it could be a series, and a long-running series in this case.

One thing that I like is having a character that I'm happy putting out there, especially for young girls. There's nothing that makes me more proud than to hear a young girl say that she wants to go into science because of the show. That makes what we do worth it to me. Yeah, so happy to be at the forefront of that.

Our female characters have bigger offices than the men, they're in science, they have a lot of power, and they're very unique people, and very good at their jobs. That's another great thing I love about doing this show.

Can you talk about the emotions as things were winding down, those moments where the emotion was overwhelming for you.

Yeah, at the end of the series, there's so many things leading up. It was like, "Our last Upfronts in New York ..." which was emotional. But OK, you get a little glimpse of it. Then we got to say goodbye over a period of time. We had so many moments over the last 12 episodes, just when we'd have a break on set, just reminiscing over the last 12 years, and things that have happened off camera and on.

So we laughed so much thinking about that: when we got shut down for singing the songs from the musical "Annie," different shenanigans -- just thinking about, like, Tamara [Taylor] cracking up, and trying to keep it together, and us all trying to not laugh in a scene. So many moments like that.

Then there's moments where, like, "This is the last scene in the lab," or "This is the last scene in our house ..." Actually, that wasn't as emotional as saying goodbye to the people. For me, when I was wrapped, I was surprised because I thought I'd be coming back the next night, and they finished me out. It was the second to last day. It was just shock, and sadness, and appreciation.

Sadness that I won't see all these people, at least not the way I have every day. I felt so appreciative of everyone and all the things we've been through together, all the crew members. People we've seen start as one position and move their way up. There's so many things like that.

You could follow the trail of tears to my trailer at the end of that night. I was a wreck, a complete wreck, because nothing really prepared me for that moment where it really ended. That was very surreal. Then, I feel OK right now, and I think when this series stops airing, I think that'll be a big cathartic time as well.

Are you free to guest star on your sister New Girl," now?

I am! They haven't called me yet. I would love to. I don't know what they would get me to play, but I'd love to be on "New Girl," for sure.