The adult members of the Losers’ Club are heading to Derry for the sequel to the box office smash horror hit “It”.

Jessica Chastain, Bill Hader, James McAvoy, James Ransone, Isaiah Mustafa, Jay Ryan and Andy Bean are all grown up and back in their hometown in “It: Chapter Two”, which picks up 27 years after the events of the first film. Now, Pennywise has returned to the sewers to once again wreak havoc on the town’s inhabitants. Landing on the cover of Entertainment Weekly‘s special Comic-Con edition, the cast opens up about the horror sequel, including some deviations from Stephen King’s novel.

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For Hader, that means his character of Richie has a different backstory.

“It’s not the same as the book but it’ll be a real mindblower,” the “Barry” star says of his character’s post-Derry life. While the rest of the cast is reluctant to spill too many details, McAvoy reveals his character of Bill is pretty much living the life author King dreamed of. “He’s in L.A. shooting a movie,” McAvoy explains.

Though the majority of the Losers’ Club has moved away and forgotten about the traumatic events involving Pennywise, Mike has remained in Derry, becoming obsessed with the past.

“Mike sees how Derry is very special in a dark way,” says Mustafa. “He’s trying to figure out what the hell’s going on in this town and what he can do to put an end to this cycle. It’s an obsession for him.”

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“When you leave Derry, something happens where you forget it all,” McAvoy adds. “I think it’s like a [power] of Pennywise’s. Because if everybody could remember what he gets up to every 27 years through history, we’d go, ‘Hey, Derry’s really f***ed up, we should do something about that. We should send in the f***ing Army!’”

Despite the horrors that unfold on screen, Chastain reveals she had a blast filming around Toronto with the cast and getting the chance to reunite with her “The Disappearance Of Eleanor Rigby” co-stars, McAvoy and Hader.

“We had so much fun. We literally sat, pretending to drink shots and eat Chinese food, for two days,” she says. “As the Losers were getting to know each other again, we were all getting to know each other.”

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But it’s not all fun and games – expect plenty of scares as Bill Skarsgard returns as Pennywise.

“He’s scarier and he’s angrier,” the actor says. “There’s a couple of very brutal things in the film.”

“It: Chapter Two” opens in theatres on Sept. 6.