'Grey's Anatomy' Boss on Season 15 Finale Cliffhangers: 'We Definitely Blew S**t Up' (Exclusive)

Grey's Anatomy
Tony Rivetti/ABC

Executive producer Krista Vernoff breaks down the biggest shockers from Thursday's season closer and that ominous final scene.

Warning: Spoiler alert! Do not proceed if you have not watched Thursday's season 15 finale of Grey's Anatomy, titled "Jump Into the Fog."

If the Seattle fog served as a metaphor on Grey's Anatomy, not everyone made it through the gloom with rosy outlooks. 

All signs pointed to a major shakeup to the status quo on Thursday's season 15 finale; after all, you can't have the doctors of Grey Sloan Memorial Hospital too comfortable, now can you? But things will look dramatically different when TV's longest-running primetime medical drama kicks off its 16th year following a flurry of season-ending bombshells.

Will Meredith (Ellen Pompeo) go through with her promise to an incarcerated DeLuca -- after saying "I love you" back, swoon -- and turn herself into police for committing insurance fraud? Will the firings of three Grey's OGs Meredith, Alex (Justin Chambers) and Richard (James Pickens Jr.) stick at Grey Sloan? With Jo (Camilla Luddington) entering the psych ward, what does this mean for her future? How will Owen (Kevin McKidd) and Teddy's (Kim Raver) new baby (and coupledom) throw a wrench in Koracick's (Greg Germann) plans? What does Amelia (Caterina Scorsone) without Owen look like?

But the biggest mystery of all revolves around the finale-ending shocker surrounding the status of Jackson (Jesse Williams), who, after a devastating fight with Maggie (Kelly McCreary), disappears into the fog. Literally. What happened to him? (Hopefully he's not lying in a ditch somewhere.) And just where did he go?  

With a flurry of unanswered questions following the cliffhanger-heavy finale, ET hopped on the phone with executive producer and showrunner Krista Vernoff, who will also run Grey's spinoff Station 19 next season, to break down the biggest shockers from the episode, from Jackson's unclear fate to Meredith's impending jail time and so much more.

ET: You set up a lot of cliffhangers at the end of this finale, the biggest one surrounding Jackson and what happened to him after he disappeared into the fog. What went into the decision behind that character being the big lingering question at the end of the season?

Krista Vernoff: I wanted a cliffhanger that would make everyone tune back in in the fall. Meredith saying, "I love you," I thought was a powerful completion moment. And while it's a little bit of a cliffhanger -- DeLuca's in jail and Meredith is going to jail -- you want to see how that is going to play out. I wanted something a little more dramatic to tag the season and it felt that disappearing Jackson into the fog felt really unexpected and it felt like the beginning [of a new journey]. It felt a little bit like in the previous scene, we completed our "season of love" and in the final scene we teased the beginning of next season.

Jackson has disappeared once before this season, without giving anyone any real notice. Is this a similar situation or is this far more dire?

I think the fact that Jackson disappeared at one point this season and the fact that he fell suddenly at the end of one act in the finale, both of those things helped mislead. You didn't expect that Jackson was actually going to disappear when he took that walk into the fog. Whereas when characters walk off into the fog on Grey's Anatomy, traditionally you get really worried. But we didn't expect Jackson to disappear again because we played that beat, had him falling at the end of act two, and because we played that story earlier this season. So I think that actually laid groundwork for this to be a really shocking end of the episode.

In the season 15 finale, Jackson Avery (Jesse Williams) disappears into the fog. Where did he go? What happened to him? - Tony Rivetti/ABC

Meredith comes clean about her role in committing insurance fraud, which landed DeLuca in jail after he took the fall for her. As a result of her confession, Alex and Richard come to her defense and take partial blame, which led to all three getting fired. It was a full-circle moment, calling back to the LVAD wire debacle in season two with Izzie. Fair to say the ramifications for this are far more serious?

Yeah. The ramifications are far more serious because Bailey just fired the three OGs. That's a thing we've never seen happen in 15 seasons of Grey's Anatomy. For Bailey to fire Alex, Meredith and Richard was really shocking to me even as I wrote it. I went into the writers' room and I was like, "You're not going to believe what just happened." But it felt appropriate for there to be real consequences and real ramifications. And we winked at the LVAD wire because these people have been together for so long and because there is so much love and friendship and mentorship there. When Richard and Alex walk into that office to back Meredith, they believe that by backing her they're saving her and that Bailey can't possibly fire all three of them. And then she does the thing they thought she couldn't possibly do.

This shakes things up at Grey Sloan for the foreseeable future. It's been a while since I've had actual questions about what the hospital will look like. Bailey made the move no one thought she would. Richard and Catherine's marriage is possibly on the rocks now. What does this mean for Grey Sloan moving forward?

I feel like we laid tremendous groundwork for season 16. All those things that you just said by watching the episode once, yeah, we blew up a whole bunch of expectations just in that last act and now nobody knows where anybody stands. Nobody knows where anybody's relationship stands and nobody knows what it's going to mean to Grey Sloan to have these three doctors be fired. Nobody knows what it's gonna mean to the series to have these three doctors fired. We're excited to get in to the writers' room and see where it goes from here, but we definitely blew s**t up.

When Meredith visits DeLuca in jail, she tells him "I love you," the first time she's said those three words to a romantic partner after Derek's death. But she also tells him that she's going to come clean and turn herself in. Do you want her to actually go through with confessing her crime and possibly go to jail? Is that a question you're still juggling with?

That isn't a question for me because the character of Meredith Grey that we've always known would never ever let someone she loves go to jail for her. She has a moral compass; it's not everybody's moral compass. She didn't share the same moral compass as Derek, for example, when she blew his Alzheimer's trials [in season seven], right? But she stuck to her own moral compass. It's like what she said to DeLuca when she broke the law, right before he said "I love you" is, "Look, I didn't think this through and maybe it was stupid, but I would do it again and this is who I am. I know it's not the easiest thing to live with but this is who I am." So I don't think there's any world where Meredith would let DeLuca sacrifice his career for her crime. I think she has every intention of going and facing the music.

Meredith Grey (Ellen Pompeo) comes clean about committing insurance fraud and as a result, she, Alex Karev (Justin Chambers) and Richard Webber (James Pickens Jr.) are fired from Grey Sloan. - Jessica Brooks/ABC

After Teddy confesses that she's in love with Owen in the previous episode, he basically proposes to Teddy right before she gives birth to their daughter, Allison. Were they always going to end up choosing each other at the end of the season?

No. We went back and forth on how this love triangle was going to play out. We talked about that story more than we talked about anything else all season in the writers' room. We went back and forth and back and forth and back and forth. Some of the writers were very firmly "Omelia" shippers, some of them were Teddy/Owen shippers and some of them were Teddy/Tom shippers, some of them were Link/Amelia [shippers]. We had a lot of fights as we figured out where that story was going to land and at the end of it, this felt right to all of us. It felt like it landed in the right place.

But you also have Koracick alone in the apartment he bought Teddy, putting together baby furniture, thinking everything's well and good...

That's why it felt right to all of us because it gave us the most possible story for next season.

Amelia tells Link she needs to figure herself out without Owen. What does this next chapter of her soul-searching look like?

What I'm most excited about in that conversation was Amelia's maturity and growth. The fact that she watched Teddy and Owen through the window and felt that grief rising and didn't shut it down by declaring her love for Link, but actually told him the truth, which is that he was a rebound who she's developed some feelings for and she dove into him too quickly on the heels of Owen. It was honest, painful and true. As she walked away and began to feel that grief, I just thought it was one of the most beautiful moments of the episode. And more will be revealed. I'm excited to explore [her journey].

Nothing is clean and tidy and perfect when there are more stories to be told. That's the reason we go from this really beautiful moment with Teddy and Owen to Tom alone in that nursery oblivious. He's a character we've come to love and care about and Amelia walking away in tears, she's a character we love tremendously and there are consequences to decisions that people make. We get to explore those in season 16.

Jo makes the difficult decision to seek professional help and her final scene shows her saying goodbye to Alex and entering the psych ward at Grey Sloan as a patient. Why did you have her journey culminate there?

Jo makes a beautiful decision to allow herself to be helped. And I think that that's a really brave thing and can only lead to healing. When you seek treatment for your mental health it can only lead to healing. I'm excited to see Jo emerge and to see how it is for Alex when Jo does emerge and how they come back together. I think it's going to be really beautiful.

Season 15 was the "season of love," do you have an idea as to what the theme is for season 16?

Not yet. I need a couple months in the writers' room before I can answer that. Ask me after the summer.

And congratulations on the two-season Grey's pickup and also taking over Station 19 duties. What are you looking forward to now that you're overseeing the entire Grey's universe?

It's really exciting. It's a new challenge and my wheels are spinning in a whole new way.

Grey's Anatomy returns Thursdays at 8 p.m. ET/PT this fall on ABC.

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