James McAvoy has confirmed filming is already under way on Andy Muscietti's It: Chapter 2.

Adapting the second half of Stephen King's 1986 horror novel for the big-screen, Muschietti's version of It is a million miles away from the 1990 TV miniseries.

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Although a lovable cast of kids made up most of the ensemble of It: Chapter 1, a new crop of actors has been cast for the adult counterparts of the Losers Club. Jessica Chastain, Bill Hader, James Ransone, Andy Bean, Jay Ryan and Isaiah Mustafa will all star alongside McAvoy, while Bill Skarsgård returns as Pennywise. With Chapter 2 heading for a September 2019 release, McAvoy has signaled the start of principal photography.

Posting on Instagram, the X-Men and Atomic Blonde actor shared a photo from the first day of filming, accompanied by the caption, "Glad you got the memo guys."

The picture of the Laughing Cow is in reference to Derry, the doomed Maine town where King's story of It is set. Although the young actors who portrayed the Losers Club are all set to return for Chapter 2, McAvoy takes one of the sequel's lead roles as an older Bill Denbrough.

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Filming is set to run throughout the summer in Toronto, and now that It: Chapter 2 has officially begun, it surely won't be too long until audiences get another terrifying snap of Skarsgård evil entertainer back in action.

With It: Chapter 1 becoming a huge hit of 2017 and the highest-grossing horror movie of all time, there are high hopes that Muschietti can deliver again. Let's hope that It: Chapter 2 "floats" when it hits theaters on September 6, 2019.