***SPOILER ALERT!!!*** 
 Ever since I first saw this movie, I've been afraid of clowns. I hate clowns! So when I read the book -being more detailed, but hell of a slow pace- it was more creepy than the movie. 
 In the summer of 1958, seven friends encountered something horrible in their town of Derry, Maine. This something fed on children, hunting them, preying on them, and devouring them. It could shape itself in any way It liked, whatever their nightmares suited, but always with one trademark: the semblance of a clown. The seven friends all had something in common: They had all escaped It at some point. And in that summer, they learned about It, confronted It, and killed It... or so they thought. 
 28 years later... A boy named Adrian Mellon is apparently thrown off a bridge by two other boys for his sexuality. It seems like an open-and-shut case, but the boys claim that there was something down below... a clown and a cloud of balloons. 
 Soon the friends are being called back to Derry, told that It is back. They made a vow, sealed in blood, to return if It wasn't dead. Each of them is now very successful, and the thought of returning to Derry, of going back to the horror that they'd all forgotten, is more than they can bear, but they had made a promise. 
 "It" is two stories being told at once. One is the story of their childhood, of their first encounter with Pennywise the Clown, their troubles with the local bullies, the impact of It upon their lives, their own personal struggles, and the eventual defeat of It. This is told from the beginning of the book to the near end of it. At the same time, the story of the return to Derry, of the research done to see what It was, the memories that were now urging to return, and subsequent events that followed which I won't spoil here. Both timelines alternate in their tellings to fit one another perfectly, even if not in perfect chronological order, and they're even further juiced with quick points of time long before their own, dipping into what else It has been up to. This construction is utterly beautiful in how it's placed, and completely builds the story up for all its plot points and climax. "It" also easily avoids a problem with many long Stephen King books: Plot threads that go nowhere. 
 The characters are completely immersive and none are the all-too-well-known cliches. Bill Denbrough is the leader of the group, with a bone to pick with It, and his own problem of stuttering. Richie Tozier has a smart mouth and a big ego, one that hides things from the others that he's ashamed of, even in denial of. Eddie Kaspbrak is asmathic and weak, but he has courage within him to help his friends. Stan Uris is a sensible and supportive friend, who helps bring understanding of things. Ben Hanscom is an overweight and loving boy who brings his own ingenuity to the group. Beverly Marsh is a tough, yet sweet girl, whose own problems at home help prepare her for what she must face with the others. And Mike Hanlon, a boy chased by the bullies for the color of his skin, who comes across the group with a desire to help, and also leading to one of the more emotional parts of the story, the Great Rock Fight. These are the seven friends whose unity and circumstances held them together against It, and who vowed to return. It isn't long before they feel familiar, as if you've known them all your life, as well as the troubles they've faced, especially those of punk and bully Henry Bowers, whose endless torment drives them into the very heart of It's lair. 
 I wouldn't recommend it if you are terrified of clowns -like me- you'll only end up in a nut house.