It: Welcome to Derry creator/director/executive producer Andy Muschietti continues to mine author Stephen King’s source novel for compelling nuggets he can expand and refine into prequel story arcs for HBO’s horrific hit limited series, having settled on the core of the first season.

Muschietti says Season 2 will explore the story of a subplot King planted in the original 1986 IT novel.  “It’s 1935 – we’re now working on it, and it’s so much fun,” Muschietti said during Deadline’s Contenders TV panel for the series. “For the ones of you who read the books, probably the Bradley Gang sounds familiar. The Bradley Gang was a gang of bank robbers that — not accidentally, but they were on their way somewhere and they stopped in Derry to buy some ammo and something horrible happens.”

King himself took inspiration from a ’30s-era true-crime incident in his Maine homebase. “The Bradley Gang is based on the Brady Gang, which is a real-life gang of robbers that were executed in the streets of Bangor, Maine,” said Muschietti. “And now we’re not creating the event that the big paroxysm of violence in this case will be the massacre of a Bradley gang.”

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He added: “There’s like three big events in Welcome to Derry Season 1 … and Season 3 would be the explosion of the Kitchener Iron Works, which is a big explosion during an Easter egg hunt where a hundred kids lost their lives. It’s always there f*cking around, so that much I can tell you.”

He elaborated: “It’s fascinating because the thing that is so much fun in this stage of development is that we’re facing an era which is the Depression Era that changes dramatically the setup of things. There’s no suburban comfort — the trope of the kids that live in suburbia and they ride their bikes and suddenly one of them disappears is nothing like this. This is in 1935. It’s a very dire situation. People are very poor. They’re struggling to survive, so the setup will be very different.”

Plumbing the intriguing nooks and crannies of the source material is the same kind of extrapolation that fueled the first season, said Muschietti, who helmed the two IT movies. “The feeling that we still had so much ground to cover. I had read this book many, many decades ago, and it was very close to me and very close to my heart. And there’s so many stories in that book that I couldn’t possibly cover in two movies.

“During the shoot of IT 2,” he added, “we kept having these conversations about the possibilities of making an origin story of, how did Bob Gray become [Pennywise] the clown? How did it become Pennywise? Who was Bob Gray? Bob Gray is one of the big enigmas in the book that are intentionally put there to create tension and are never solved. Our idea was to just like open another window into that enigma.”

Check back Monday for the panel video.