You die if you try.
The story of Stephen King's It may not be new--the book is over thirty years old after all--but given how different the most recent movie adaptations are from the source material, it's a given that the ending would have some pretty major departures as well. How do the Losers manage to face down the nightmare that is Pennywise once and for all this time around? Where do they end up after the fact? How does the new movie stack up to the '90s miniseries and the original novel in terms of concluding each Loser's individual story?
Get ready for some major It Chapter 2 spoilers as we break down exactly what it took to destroy the monster that devoured the children of Derry, Maine every 27 years.
It Chapter 2 Coverage
The adult Losers--minus Stan, who, in keeping with his story in the book, killed himself before the reunion--eventually find their way back to Neibolt House, where they retrace their steps from 27 years ago. They wind up back in the sewers, but things are different in Pennywise's cistern-based nest this time. There's no longer a giant stack of debris surrounded by floating bodies. Instead, there's a wooden hatch that the Losers are able to open and climb down into the place where Pennywise actually arrived from space millions of years ago.
Think the Lighthouse cave from the movie Annihilation and you'll be in the right ballpark for what this strange new cave actually looks like--lots of oil-slick colored rock protrusions and surreal lighting effects, coupled with some warping, maw-like caverns in the ceiling.
It's in this sub-sewer area that the Losers are able to attempt the Ritual of Chüd, which involves them all burning "tokens" from their past and then chanting "turn light into darkness" as they hold hands around a ceremonial leather jug which Mike says will be able to trap the deadlights--Pennywise's true form. Bill's token is Georgie's boat, Bev's is the poem Ben wrote her, Richie's is a literal token from the arcade he played Street Fighter in, Mike's is the rock that hit Bowers from the rock fight in 1989, Eddie's is his inhaler, and Ben's is the page of his yearbook that Bev signed. They use a shower cap for Stan, given context by a flashback earlier in the movie where it's revealed that Stan was afraid of getting spiders in his hair in their underground clubhouse as a kid.
Unfortunately, things don't actually work according to Mike's plan, and rather than trapping the deadlights, the Losers only succeed in summoning Pennywise himself into the nest area. He attacks, sending each Loser off into a new individual nightmare which nearly kills them before they each manage to fight their way back to the nest. During the final confrontation, Mike is nearly killed, but Richie manages to distract Pennywise long enough to save him--a move that gets him caught in the hypnotic deadlights, just like Bev had been 27 years ago. It's Eddie who finds the courage to rush to Richie's aid, throwing a piece of wrought iron fence like a javelin into Pennywise's maw.
Eddie rushes to Richie's side, believing he's killed It, but as he's leaning over Richie's body, Pennywise skewers him with a claw and flings him across the cave. The Losers frantically try to save him, while Eddie chooses that moment to tell them that, earlier, during another Pennywise nightmare where he saw the leper from his childhood, he was certain he could kill it. He confesses that he almost choked it to death. This inspires the Losers to attempt a new plan--they'll "make Pennywise small," first literally, by forcing him into tight quarters, and then metaphorically when that fails, because they realized, with Eddie's help, that Pennywise functions primarily on belief.
It's not completely clear why or how this revelation is different from the similar revelation they had as children when they began to beat Pennywise to death almost three decades ago. Apparently getting pummeled by children was less effective than being yelled at by adults.
They (minus Richie, who at first refuses to leave Eddie's side) begin hurling insults at Pennywise, proclaiming that he's not scary or dangerous at all, which miraculously begins to shrink Pennywise down into a pathetic blob. When Pennywise is weakened enough, Mike reaches in and tears its heart out, holding it for all the Losers to crush in their hands.
With Pennywise defeated, the nest begins to collapse. The Losers are forced to leave Eddie--who died as Pennywise was killed--behind as they escape, dragging Richie away as he yells "we can still help him!" Neibolt House collapses into a sinkhole as they stumble outside.
With their ordeal over, the Losers immediately head to the quarry, where they re-live their childhood by jumping off the cliffside into the water to wash the mud and blood off themselves. Richie, still grieving Eddie's loss, sits in the water and sobs as the other Losers gather around him. Eventually, Bev and Ben finally share a kiss after Bev was able to remember that it was Ben, not Bill, who wrote her secret admirer poem all those years ago.
When the Losers leave the quarry, they realize the scars on their palms are gone. Their oath is finally fulfilled.
Each surviving Loser is then given a brief epilogue. Mike, finally satisfied that the job is done, leaves Derry. Bill returns home--presumably to his wife--and begins a new book. Ben and Bev move in together onto a yacht with a dog. Richie returns to Derry's Kissing Bridge, where he secretly carved his "R + E" love confession for Eddie when he was a child and re-carves the E. Each Loser gets a letter from Stan, which is read as the final narration. He admits that he killed himself because he was too scared to return to Derry and he knew they wouldn't be able to defeat Pennywise if they were all alive and not there--so he "took himself off the board."
Why Stan decided that the fear of being killed was somehow worse than actually killing himself isn't exactly clear, but the tone of the scene is deeply sincere and meant to feel nostalgic and sweet rather than tragic. (It is extremely tragic.)
Unsurprisingly, there are no post-credits stingers or special moments after the credits roll. The story has reached the end of the source material, for one, and everyone (except Stan, Eddie, and Richie--so, uh, 4 out of 7) managed to get their happy ending. This time around--unlike the novel--the Losers don't intend to forget their friends or their experiences when they all go back to their lives, as Mike explains, "because they have more they want to remember."