The character is an ancient, trans-dimensional evil entity who preys upon the children (and sometimes adults) of Derry, Maine, roughly every 27 years, using a variety of powers that include the ability to shapeshift, manipulate reality, and go unnoticed by adults.
While this version of It is currently Pure Evil just like the novel and the TV miniseries incarnations, there's a slight possibility that this may change once Welcome to Derry, an upcoming HBO Max prequel show about its origins set in the 1960s is released, as the series will delve into its backstory.
Well, that's not super easy to answer, but let's give it a try. In both the book and the films, It is an ancient alien creature, older than civilization, and in King's novel, older than our universe. It feasts on the flesh of humans simply because our fears are easy to manifest and they make us taste better.
In both the book and the films, It is an ancient alien creature, older than civilization, and in King's novel, older than our universe. It feasts on the flesh of humans simply because our fears are easy to manifest and they make us taste better.
Pennywise is Older than the Universe Itself
According to the novel, Pennywise existed long before The Big Bang in a dimension known as Macroverse. After crash landing on Earth, he entered a state of hibernation and awoke in early 18th century America to sustain himself on human victims before returning to his slumber.
In their final battle, the Losers' Club was able to kill Pennywise by reducing him to a child-like form as they overcame their fears. In the moments before Pennywise died, his fear is reminiscent of Georgie's own, therefore closing the cyclical nature of Pennywise's murders.
Pennywise kills not because it is mentally insane or, because it's just evil. It kills because it can only eat every 27 YEARS. To satisfy her hunger she eats kids every 27 years.
IT arrived on Earth through an event similar to an asteroid impact, landing in what would later become Derry, Maine. Once there, IT adopted its usual pattern of hibernation that lasted between 27 and 30 years, awakening to kill and eat and then going back to sleep.
Stephen King's IT introduced readers to a one-of-a-kind creature that can take any form, the most common one being Pennywise the Dancing Clown, and as menacing as it is, this creature has one big enemy it's truly scared of: Maturin, the turtle.
However, It must surrender the the laws of whatever shape It takes. Pennywise's strength is also his weakness. For example, if he were to take the shape of a werewolf (as he does in the novel), silver bullets would harm him.
Originally Answered: Why did Pennywise start on Chapter Two with attacking an adult? Pennywise thrives on fear. By killing him, Pennywise gets the town starting to fear others. Setting the stage for his return.
Literature. In the novel, It is a shapeshifting monster who usually takes the form of Pennywise the Dancing Clown, originating in a void containing and surrounding the Universe—a place referred to in the novel as the "Macroverse".
King decided for IT to predominantly take the shape of Pennywise the Dancing Clown because he believes "clowns scare children more than anything else in the world." IT influences the adults of Derry to passively ignore it and not interfere with his attacks on Derry's children.
The Losers confront Pennywise on how they've overcome their fears, and are no longer scared of the entity, causing It to shrink to a small weakened Pennywise. Mike rips out It's heart, which he and the Losers crush with their bare hands, finally killing It.
Thanos would absolutely decimate Pennywise. Thanos is a fearless, ruthless, cunning, Machiavellian nihilist. He only fears one thing, the rejection of the one entity that he loves, Death, or the Marvel embodiment of Death.
It disguises itself as many frightening things in the movie. Pennywise can morph his mouth into a giant gaping mouth with layers of sharp teeth which he uses it mangle and eat his victims.
Also in the 2017 film, Georgie's death is changed. As well as having his right arm bitten off, Georgie is trying to crawl away but he was dragged into the sewers and devoured by Pennywise, with an unnamed older woman and her cat being the sole witnesses of the horrific scene, including before Georgie lost his arm.
In the novel, It's origins are nebulous. He took the form of a clown most frequently, Mr. Bob Gray or Pennywise, but his true form is an ancient eldritch entity from another universe who landed in the town that would become Derry by way of an asteroid and first awoke in 1715.
Though there are some IT characters just as scary as Pennywise, the film's main villain proves to be its deadliest, with a kill count that actually reaches into the tens of thousands. Reddit user u/angelholme estimates that Pennywise actually took the lives of between 12,117 and 18,011 people.
They reach the conclusion that Pennywise has all of the adults under some sort of spell that prohibits them from seeing him. The adults of Derry are shown to be villainous in their own right as well. The adults of Derry are shown to be true villains of the story in the same way as Pennywise.
The rest of the group realizes they can defeat it by shrinking it and therefore weakening it, which they achieve by standing up to it. They take out IT's heart and proceed to crush it, finally killing it. Eddie dies and his body is left behind.
Now, when the Losers crushed IT's heart while in its spider form, they killed IT's physical form and severed its connection to Derry, thus why the town was destroyed, but the true entity still lives in another plane of existence.