Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Exposition
From Hell to High School
Nikki has problems. She spent six months (which felt like a century) in the Everneath getting her emotions sucked out by immortal Cole, but now she's back in the ordinary world and her life is in shambles. Her family life is a mess, her boyfriend, Jack, is acting like she's a stranger, and Cole keeps bugging her about becoming an immortal like him (which would mean stealing other people's souls to survive). With all this drama, we're seeing Nikki set up for a tale of forgiveness, redemption, and heaps of messed-up emotional stuff.
Rising Action
The Emotional Merry-Go-Round
While resisting the temptation to go with Cole to the Everneath, Nikki tries to make her dad happy while also patching up her friendship—and maybe her relationship?—with Jack. But she gets caught in a web of her own lies when Cole spills the beans to Jack about how Nikki is actually doomed to return to the Tunnels soon. And when he does, Jack leaves town. So just as Nikki thought things were coming together, her world begins to fall apart. Again. Sounds like enough trouble to constitute some rising action, eh?
Climax
Hold Your Breath As We Go Through the Tunnel
The Tunnels are coming for Nikki within a matter of days. Jack shows up and forgives her, and they hatch a plan to try to defeat Cole. Will it work? Sadly, no dice. But when the Tunnels come, Jack takes Nikki's place, jumping into them and vanishing from this world. There's all this suspense leading up to this point, which is why we're calling this the climax, not to mention all the emotional resonances of Jack and Nikki's last few days together now that they've reconnected.
Falling Action
Loved But Alone
Jack is gone, and Nikki can't believe it—Will, Jack's brother, gets her the heck out of there. Nikki knows that Jack sacrificed himself for her because he loves her, but that doesn't make it any easier for her to deal with the emotional aftermath of the event. That said, the threat of the Tunnels, which has haunted Nikki throughout the book, has finally subsided. This means we've officially entered falling action territory. Just as we built up to the climax of the Tunnels coming, now we're starting to wind down from their arrival.
Resolution
Dream a Little Dream of Me
Nikki is learning to live without Jack in her life… but she's also dreaming of him every night. Their emotional connection sustains him in the Tunnels, and gives her the resolve to find him someday. Just as he anchored her, so, too, does she anchor him. Nikki also repairs her relationship with her family, and tells Cole to stay away from her. These events all wrap up the main tensions of the story, which is why they're in the resolution section.