Why It: Chapter 1 Is The Highest Grossing Stephen King Movie (By Far)

screenrant.com:

There have been numerous movie adaptions of Stephen King books over the years, but It: Chapter One had the biggest box office impact by far. Set in the fictional and cursed town of Derry, Maine, It tells the story of seven friends (called the Loser's Club) who battle a demonic shapeshifting entity known primarily as «Pennywise The Dancing Clown» first as children and then as adults. It was first adapted in 1990 as a television miniseries, and although Tim Curry's portrayal of Pennywise left a terrifying legacy, the miniseries itself is often regarded as a cheesy product of its time that brushed over some of the more horrifying elements of the novel.

In comparison, the two movie adaptions released in the late 2010s had a much darker tone, delving deeper into the horrors — both supernatural and human — that the Loser's Club faced. Although It: Chapter Two was inconsistent and problem-filled, the 2017 film (sometimes referred to as It: Chapter One), which focuses solely on the group as children, was critically acclaimed upon release. Along with being well received by critics and audiences alike, It was also a box office success, grossing higher than other King adaptions by a wide margin.

Related: Everything Stephen King’s It Got Right (That Chapter 2 Got Wrong)

It: Chapter One was released at exactly the right time, when the success of shows like Stranger Things had opened up a market for eighties nostalgia, something that It: Chapter One was able to perfectly encapsulate without feeling overbearing.By changing the timeframe of the novel (in King's book, the Loser's Club are children during the 1950s), It: Chapter One capitalized on a perfect opportunity and was able to bring a fresh perspective to the story.