Describe

Bill, Beverly, Richie, Eddie, Ben, Stan and Mike form the "Losers Club", a group of social misfits who meet and form a tight-knit friendship. Each of the children come into contact individually with the child-killing clown haunting their hometown of Derry, Maine. The monster, which the group later collectively name "It," usually appears as the thing the child victim most fears before taking the form of Pennywise the Dancing Clown (the same clown that killed Laurie Ann in the opening scene). Their separate encounters are later fortified when they all witness Pennywise reach out from a photograph in an album owned by Mike Hanlon, one of the children.

Spurred by Bill Denbrough's desire for revenge on It for killing his younger brother Georgie, the Losers resolve to locate It's home in the sewers and destroy the threat to Derry once and for all. Henry Bowers, a mentally disturbed bully, and two of his friends – Victor Criss and Belch Huggins – follow the group into the Barrens and into the sewers, in a bid to ambush and kill them as revenge for an earlier rock fight. During their trek through the sewers, Stan Uris, one of the Losers, is pulled away from the group by Henry and Belch, and Henry pulls out a pocketknife. Victor has been ordered to ambush the Losers from another side but is killed by It.

As the remaining Losers come to the middle of the sewers they discover Stan is missing. Belch restrains Stan as Henry prepares to kill him with the pocketknife, but It bursts through a sewage pipe and kills Belch while Henry and Stan watch in horror. As It makes its way out of the pipe, Stan flees and Henry's hair instantly turns white from the sight of It's true form.

Stan meets up with the Losers, telling them that It's true form is far more reprehensible than Pennywise and they avoid looking into It's deadlights. It vanishes, and smoke fills the chamber. The seven form a circle, although It attempts to distract and break them apart by simultaneously appearing as Georgie, Beverly's father and a werewolf. As It, in the form of Pennywise, attempts to eat Stan, Beverly cracks the monster's head open with a silver slug (formed from a pair of Richie's mother's earrings) fired from a slingshot, revealing the bright deadlights underneath. However, before the children can kill It, Pennywise summersaults through the air and escapes by getting sucked through a drain in the floor. The group grab his arms, only for the glove and one of the clown's claws to rip off, revealing a larger 3-fingered claw. After arguing and deciding It is dead, the group exits the sewers and make a promise to return and fight It, should It ever return.