The spider-clown shrinks as the Losers hurl taunts at It, until it's tiny and weak enough that they pluck out its heart and squash it into nothingness. In the end, they defeat Pennywise by, uh, making him feel really bad about himself. It author Stephen King.
According to It, when humans got scared, "all the chemicals of fear flooded the body and salted the meat". This is why he prefers to feast on children -- their fears are simple, pure, and powerful compared to the complex, pathological fears of adults.
Bill learns that It can only be defeated during a battle of wills, and sees It's true form, the "Deadlights", before Bill defeats the monster with Maturin's help. After the battle, not knowing if they killed It or not, the Losers get lost in the sewers.
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.
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.
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.
 Skarsgård's appearance and performance were naturally creepy, but It director Andy Muschetti still wanted to ensure that he captured the genuinely fearful reactionsOpens in new tab of the film's young cast.
Throughout the book, It is generally referred to as male, usually appearing as Pennywise. The Losers come to believe It may be female after seeing it in the form of a monstrous giant spider that lays eggs.
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.
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.
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.
And if his victim believes him to be powerless, he will become powerless. And so the group figures out that their best bet is, essentially, to bully the bully: They mock Pennywise, telling him he isn't scary. Humiliated, Pennywise begins to shrink, transforming into an almost Benjamin Button–like, melted clown-baby.
Some time after the universe was created, Pennywise made Its way to Earth, crash-landing in what would eventually become Derry, Maine. Once it became inhabited with people, Pennywise began Its infamous quarter-century cycle, awakening from hibernation every twenty-five to twenty-seven years to feed.
He's a demon and the general idea is if you are not scare, it will only be harder for Pennywise to kill you as he needs to bait you. He can kill you if he wants to anytime and doesn't care. Although, if you are not scared, he will either leave you be for a little while or just kill you in the instant .
It was said on page 1361 that the Spider being both female and pregnant was a symbolic interperetation. Its not literal, but a representation of whatever equivalent but inconceivable reproductive capability It actually has. Pennywise didn't become pregnant.
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.
Kersh is Pennywise's daughter. Or at least the daughter of the man who originally had Pennywise's face. Additionally, the trailer offers a first glimpse of Bill (James McAvoy), Ben (Jay Ryan), Richie (Bill Hader), Eddie (James Ransone), and Mike (Isaiah Mustafa) back together.
However, despite all that, there's one thing IT doesn't feature, and that's Pennywise devouring a baby. King doesn't go quite that far, although babies aren't safe from violence in the book completely, thanks to Patrick Hockstetter.
Although the phrase is represented differently in the book and the movies, it has the same meaning in both, as it's Pennywise's way of subtly telling its victims (mostly young children) that they will die. As mentioned above, IT lives in the sewers of Derry, and that's where it takes most of the bodies of its victims.
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.
Every 27 years, a shape-shifting entity known as IT crawls out of the sewers to prey on the children of Derry, Maine. IT plasters himself with an unnatural grin, takes on the form of Pennywise the Dancing Clown, and wreaks havoc.
Georgie reaches for it, only for Pennywise to grab his arm and sink his massive teeth into it. The creature rips off Georgie's arm and leaves him crying for Bill before dragging him down into the sewers.
Twenty-seven years after their first showdown with the murderous clown, the now-grown members of the Losers' Club converged on Derry to defeat Pennywise forever. 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.