9-1-1 showrunner explains that 'important' death — and previews the second half of season 6

9-1-1 showrunner and executive producer Kristen Reidel promised that Monday's midseason finale would be "fraught," and the episode definitely delivered.

While "Red Flag" was buoyed by the news that Buck (Oliver Stark) is going to become a biological father and Chimney (Kenneth Choi) and Maddie (Jennifer Love Hewitt) finding their dream "murder house," it was a distressing episode for most of the 118 — with Hen (Aisha Hinds) worried about how she and Karen (Tracie Thoms) will tell their son Denny (Declan Pratt) about his biological parents, and Bobby (Peter Krause) reeling from the death of his sponsor, Wendall (Grey's Anatomy's Maurice Irvin).

With so much to process, we asked Reidel to break down the biggest moments from the winter finale and preview what's to come when 9-1-1 returns for the second half of season 6 in the spring.

Buck becoming a biological dad

KRISTEN REIDEL: When Buck made this decision to be a sperm donor, it came from a sort of selfless place. He saw two people who needed help and he had the ability to help and he thought, "Of course I should help these people." But I think he never really considered what he did or didn't want to get out of it. And now it's not a theoretical kid. He'll have a lot to figure out as this baby gets closer, because with sperm donors, the relationship can vary: some are never known, others are involved in the life of the child. I think the question for Buck going forward is, "Why did I say yes to this?"

Maddie and Chimney find their "murder house"

In a lot of ways, Maddie moved into Chimney's apartment that he lived in for a very long time, and that's obviously where they had [their daughter] and where they've been living together this last year. But this house is really a fresh start and a new beginning. It's their place, it's the home that they're going to create together for their daughter. It's a new level of commitment for them. And it's also it's a really nice house — a little scary when you first look at it, but it's going to fix up great.

Hen and Karen's son tracks down his biological father, Nathaniel (Troy Winbush)

Denny finds the information [in Hen and Karen's files] and shows up and knocks on his door. It's so complicated, because clearly Denny has questions and he wants to know about where he came from and who those people are that gave him life. But on the other hand, he really loves his mothers and doesn't want to hurt them so he's trying to figure out. He's trying to get answers to the questions without involving his moms — which is an understandable decision, but probably not the best one. And then Hen and Karen want to help him and answer his questions, but it's hard. It's a very tricky dynamic there.

Peter Krause in the “Red Flag” episode of 9-1-1
Peter Krause in the “Red Flag” episode of 9-1-1

Jack Zeman/ FOX. Peter Krause on '9-1-1'.

Bobby loses his sponsor

Bobby is in recovery and Bobby will always be in recovery. It's a huge part of his life and who he is as a person. It's not the only thing, but it is a big chunk of it. And [Wendall's death] felt like an interesting way to talk about that without Bobby falling off the wagon. Wendall was a very important part of the person that Bobby is now, and the life that he has now. In a lot of ways, Wendall didn't just impact Bobby's life, he impacted the family's life — because Bobby had Wendall to turn to instead of turning to drugs or alcohol, and that made their life better.

In the back half of the season, as Bobby is kind of searching for the truths about what really happened to Wendall, we'll get to see some of that relationship. We'll get to see the two of them meet and we'll get a sense of that relationship with Wendall meant to Bobby, and also to [Angela Bassett's] Athena. We'll see Bobby and Athena — and a little bit of [Corinne Massiah's] May — try and figure out what happened to Wendall, but also what's going on at this facility that should be helping people but it seems like is maybe abusing them.

What else to expect from season 6

Craziness. When we come back, we're going to be dealing with an unusual weather issue, which is basically thunder and lightning without rain — lightning that strikes out of nowhere and creates some emergencies. Our 118 people will get caught up in that, and that will be our big start to the back half. And then for the rest of the season, we're going to have some episodes like you would expect, and then we have some different things that we've never really done before. Hopefully there'll be something for everyone.

9-1-1 returns this spring.

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