The Note Left Behind

The Tree house

Sasha's backyard bordered a stretch of undeveloped woods that the town had never gotten around to selling, and somewhere in the middle of it, half-collapsed into a big oak tree, sat a tree house that had clearly once belonged to someone's ambitious childhood project.

"My brother built it," Sasha said, the first time she brought him there, climbing the ladder with the ease of someone who'd done it a thousand times. "Before he left for college and stopped caring about anything that wasn't three states away."

It was small, wood soft with age in places, but sturdy enough, with a single window that looked out over the treeline toward, if you squinted, the very edge of the school's back parking lot.

"Nobody else knows about it," Sasha said, dropping onto a folded blanket that had clearly lived up here a while. "Not since my brother left. It's just — mine. Ours, I guess, now."

Nathan understood immediately why she'd brought him here instead of anywhere else. It wasn't just privacy. It was distance — a place far enough from school, from the hallway outside Callahan's door, that they could say things out loud they wouldn't dare say anywhere closer.

"We need a plan that isn't just staring at his classroom door," Nathan said, settling across from her.

"I have a plan."

"Why doesn't that reassure me?"

Sasha grinned, pulling a battered folder from her backpack — the same one that now held the note, several pages of handwritten notes, and, Nathan noted, an increasingly incriminating printout of old staff records. "The archive project isn't done. We still have three more boxes of yearbooks to go through. Old ones. From back when Callahan would've been young enough to fit the timeline."

"You want to keep digging through the archive room."

"I want to keep digging, period. The archive room's just where the shovel is."

Nathan looked at the folder, then at her — the stubborn set of her jaw, the way she'd clearly already made up her mind days ago and was just now getting around to informing him of it — and felt the last of his hesitation give way to something that felt less like reluctance and more like resolve.

"Okay," he said. "Where do we start?"

Sasha's smile widened, warm and a little relieved, like she hadn't been entirely sure he'd say yes.

"Ten years back," she said. "That's where the yearbook photos start looking recent enough to matter. That's where we start looking for M."

Below them, through the treehouse's single warped window, Nathan could just make out the distant glow of the school's back parking lot lights flickering on as evening settled fully over the woods. It was strange, he thought, how close they still were to everything — the school, the hallway, Callahan's classroom door — and yet how completely separate this small wooden box felt from all of it.

"You're quiet," Sasha said, watching him.

"Just thinking."

"About the plan?"

"About how weird it is that we're planning this in a treehouse like we're twelve, not seventeen."

Sasha laughed, the sound bouncing softly off the low wooden ceiling. "Would you rather plan a potential exposure of institutional cover-up somewhere more dignified? My kitchen table, maybe? With snacks?"

"Snacks would help."

"Next time," she promised, already reaching for her backpack to grab the first of the yearbooks they'd smuggled out of the archive room earlier that day. "Tonight, we work with what we've got."