The first installment of BBC and Starz’s harrowing “The Missing” ended with a descent into madness, but don’t expect a resolution to any lingering questions in the follow-up.

Created and written by brothers Harry and Jack Williams, the eight-hour second installment of the missing persons limited series launched Oct. 12 in the U.K. and will make its international bow at Mipcom. This time the show follows an all-new case involving Sam (David Morrissey) and Gemma (Keeley Hawes), whose daughter disappeared in 2003. In 2014, Alice (Abigail Hardingham) returns. The thriller will toggle between 2014 and the present as returning French detective Julien Baptiste (Tcheky Karyo) gets involved in the story.

At what point did you decide there would be a season two?
Harry Williams: We always imagined it would be one series and it was midway through series one when we realized we wouldn’t be able to write about Julien, who we just loved. We had more to say with him and felt his story wasn’t told and there were themes and ideas we hadn’t explored about loss and tragedy.

Was there ever thought given to continuing the story with the other season one characters?
Jack Williams: We had the end of series one in mind from the moment we wrote episode one, but we talked about it occasionally. We thought about possible ways we might go, but we always went back to the fact it wasn’t the way the story was designed and we felt like we’d be betraying the story of the first series just for the sake of doing more and that didn’t seem right.

Why bring back Julien?
Jack Williams: He was such a breakout character for us in the first series and so integral to events in the first series but he didn’t pivot as much as you might think. He doesn’t say much about himself. You get a sense he’s got a life-long history and it seemed the obvious thing to do was unpack the character we met in series one.

Harry Williams: He’s got a huge, emotional through-line in this series. … He’s as much the heart of the story as our hero family.

What’s the theme of season two?
Harry Williams: What happens when a child who’s been missing comes back? That’s a completely different thing. It’s supposed to be a happy ending, but is it? It starts out with this person who’s been imprisoned for 11 years. What does imprisonment or freedom mean in terms of relationships and how we imprison ourselves? We sort of try to explore that through all the stories and characters this time around.

What did you learn from reactions to the finale of season one?
Harry Williams: Some people thought we were going for a cliffhanger, which wasn’t the intention. In our minds, given the journey of the characters and the investigation that’s taken place, it’s pretty evident the kid had died. We leave maybe a 5% possibility that maybe he’s still out there as something for Tony to latch onto to keep him searching. In all these cases, it’s never cut and dried, never tied up in a neat bow where you get the body. We wanted it to be truthful, but allow these characters to explore what that looks like.

Jack Williams: I would say the ending of season two is very different. It does feel very complete. I don’t think questions are left. It’s a different show that requires a different ending. And you don’t want to repeat yourself. There are more things that need wrapping up and we just watched a couple [of episodes] today and we’re very excited how all these questions are answered. It’s got a very different feel.

What are the odds of a third season?
Jack Williams: Never say never. We love the show and the world of the show. We don’t have an idea for a story we want to tell at this moment. We wouldn’t rule it out but it’s not on the horizon anytime soon.