NCIS Boss Breaks Down That Shocking Return In Fall Finale: 'We'd Been Talking About The Idea For A Year' — Plus, Grade It!

Warning: This post contains spoilers for Tuesday's "NCIS" fall finale.

It's December... and an "NCIS" fan favorite is coming home for the holidays.

At the end of Tuesday's fall finale, Vance called Jess to tell her she finally got her first assignment for NCIS Elite, and her first target is... former team member Ellie Bishop! (Emily Wickersham, who played Bishop, left the series in Season 18 after an eight-season run, with Bishop joining a top-secret undercover operation.) Jess was stunned to learn that Bishop is her target — and Bishop herself could be seen spying on the team, with Wickersham making a brief on-camera appearance before the credits rolled.

What has Bishop been up to all these years? What kind of trouble is she in now? And how will Nick react when he learns that his former flame is back in the picture? We posed all of these questions and more to "NCIS" showrunner Steven D. Binder, who filled us in on Bishop's return and how it will impact the rest of the team. Read on to get the scoop!

TVLINE | How long had you been toying with the idea of bringing Bishop back?
You know, as soon as they leave, it's: "When can you come back?" I'd say we'd been talking about the idea for a year, and then it's: Do they want to do it? When can they do it? I mean, [Bishop] was part of the pitch at the beginning of the season. You know, pie in the sky, this is what we'd like to do. We've been talking about it. Now we want to actually do this, and then whether or not it's going to happen, you don't ever really know, because timing is a big piece of it, and [Wickersham] lives, you know, not here anymore, so that makes it difficult. But she was game. She wanted to come back. I had a conversation with her... and she was gung ho. And that never faded throughout the process.

TVLINE | So Jess is told that Bishop is the target of the mission. Does that mean she's a criminal suspect? What can you tell us about the actual case?
I can tell you that she left on a pretty dangerous, interesting mission in a foreign land, and she has been doing that kind of work since then, and it's taxing and it's trying, and it's deadly, and people die, and you're responsible for people dying. You're not at the Four Seasons, and she is not the same person. I mean, in some way, she is. She still likes her Klowny Kakes. [Laughs] But she is not the same person that left the show. She's a very different person. A lot has happened to her, and that will go a long way to explain why we are looking for her in a way that suggests she's done something wrong.

TVLINE | So she's been kind of hardened by her time undercover?
Yeah, and she has done something wrong. The question is: What is her motive? And that's what we will explore.

TVLINE | Bishop and Nick had a thing going on, but it ended when she left the team and went undercover. So how would Nick theoretically react to knowing that Bishop is back?
Well, I would refer you to that last scene between them, where not only was she leaving, she was going to leave without saying anything. She was going to leave and let him believe her cover story, which is that she's committed a crime. Now duty says that she has to do that. But I'm pretty sure people who are married to someone they trust, who work at high levels of the government, tell their spouses s**t they're not supposed to tell them. I know that they're probably breaking the law by doing so, but my God, it's your wife or your husband. So if I'm Nick, I might be a little annoyed that I was not told. And I think that's how he feels: She left. She lied. She wasn't going to say goodbye. How would anyone respond when this person suddenly shows up? And I think Nick's not going to surprise us.

TVLINE | And of course, Jess is instructed to keep this secret. So how does holding on to that secret affect her relationship with Nick?
I can tell you two things. One is: We won't have to worry about that too long, because circumstances will dictate that we don't go down that road. But I can also tell you that Knight doesn't make the same choice Bishop made. Knight chooses team loyalty over her oath, over her duty. Revealing classified information is probably not legal, but you know... see aforementioned conversation about talking to your spouse.

TVLINE | We did see Bishop spying on the team from afar at the end of the episode, so we know she's back in the flesh. How much will we see of Emily Wickersham in the back half of the season? Is she a series regular? Just a guest star?
We're gonna run this story out and have it end, so expect to see her right now in one episode that will run it out. We have no official plans right now to continue that storyline, but we had a great time with Emily, and Emily had a great time here. So she's sort of back on the roster, so to speak. But we've done some very long arc stories that have run out. This is not going to be one of them. We're going to go right to what people want to see, and we're going to have some closure, although that may or may not be what people want to see. We'll find out.

(Binder later clarified that the door is always open for Wickersham to return as Bishop: "She had a great time. We had a great time. It's a fun story. The character is because of her... [Bishop] always was an interesting character. She's a way more interesting character now, because of the wear and tear on the psyche.")

Alright, "NCIS" fans, it's your turn: Give the fall finale a grade in our poll, and then hit the comments to share your thoughts on the big Bishop reveal.