Just when you thought it was safe to go exploring in the sewers of Derry, Pennywise the Dancing Clown is back in IT Chapter Two. New footage from the movie was screened at San Diego Comic-Con's horror preview night ScareDiego, and Warner Bros. also released a creepy new poster for IT Chapter Two ahead of tomorrow's trailer release.

Like the first installment, IT Chapter Two was directed by Andrés Muschietti, and the original cast of kids returns alongside Pennywise actor Bill Skarsgård. The sequel picks up 27 years after the events of IT, with the Losers' Club fulfilling their promise to return to Derry and put a stop to It once and for all. The adult cast includes Jessica Chastain as Beverly, James McAvoy as Bill, Isaiah Mustafa as Mike, Jay Ryan as Ben, Bill Hader as Richie, James Ransone as Eddie, and Andy Bean as Stanley. A teaser trailer for IT Chapter Two has previously been released, showing a visit home for Beverly that soon turns terrifying.

Related: IT Chapter Two: Cast & Character Guide

During a panel hosted by Conan O'Brien, Muschietti and the adult Losers' Club cast members shared anecdotes from the production. They gave the audience a first look at the new trailer, and also offered an exclusive look at three scenes from IT Chapter Two. In the footage from the first scene shown, the Losers' Club meet up again after almost three decades at a Chinese restaurant. They exchange banter, but things take a dark turn when they open their fortune cookies. Nerds of Color says that the scene was "creepy as f***" and that "everyone had chemistry with each other," while Eric Goldman noted that there are "lots of great character beats." Muschietti revealed that he got his first choice for every one of the adult cast, since every person who asked said yes to the movie.

Check out the new poster for IT Chapter Two below:

IT Chapter Two Pennywise poster

In the second scene from IT Chapter Two, the adult Bill is in a carnival funhouse trying to save a child from becoming Pennywise's next victim. According to Eric Goldman, "things quickly get very trippy and then very intense as Pennywise makes his presence known." Nerds of Color described the scene as "horrifying." This scene was created for the movie and does not appear in Stephen King's novel.

The final scene shown was the adult Losers' Club returning to the Neibolt house - the creepy old abandoned home where they had a terrifying showdown with Pennywise in the first movie. Several audience members noted an homage to John Carpenter's classic horror movie The Thing in this scene.

The trailer for IT Chapter Two also got a strong response from the crowd. Rachel West said that the trailer "deserves a standing ovation," while Eric Goldman noted that "It seems like they added a lot of freaky stuff not in the adult sequences of the book and it looks really good." So, while some sequences - like the attack of a giant Paul Bunyan, Beverly's visit with Mrs. Kersh, and the scene at the Chinese restaurant - will be familiar to book readers, even hardcore King fans should brace for some surprises.

If you want to see some of the terror for yourself, stay tuned to Screen Rant tomorrow morning, when the trailer for IT Chapter Two will be released online.

More: IT Chapter Two Trailer Breakdown - 15 Story Reveals & Secrets

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