Is 'IT: Welcome to Derry' based on Stephen King's book?

Pennywise lives, and it won't be long before we meet everyone's least favorite clown beneath the sewers of Derry once more.

But given we've already had two IT movies that largely covered the events of Stephen King 's famous novel, what is HBO Max's new series IT: Welcome to Derry going to be about?

We've seen from the trailer that Pennywise (Bill Skarsgård) will return, and that a bunch of new kids will be banding together to face him — but how exactly does this tie in with the movies and book?

We've broken down everything we know so far below.

Is IT: Welcome to Derry based on Stephen King's book?

Our biggest clues as to what IT: Welcome to Derry will be based on, alongside the trailer, comes courtesy of the official HBO Max logline and some helpful interview quotes from e