Stevie tapped her ID on the door panel and pushed her way into the art barn silently, leaving Germaine in the dark.

The workroom in the art barn was now home to a large, strange contraption. Vi was hanging a wooden sign that read “RUBE’S DINER,” while Janelle moved around, checking things with a level. Janelle had taken the budget the school had granted her and also raided the castaways from the dining hall to create her machine. The poles had been put into place to make a frame that held gently tipped shelving, on which stacks of plates and cups and been glued into carefully calculated arrangements. There were small tables, deliberately angled chairs with more piles of plates and cups balanced on them. There were several old toasters and a board painted to represent a soda dispenser. Everything was connected by some plastic tubing that looked like the circulatory system of this diner version of a Frankenstein’s monster.

Nate looked up from his computer.

“That was a long talk you had,” he said.

“I went to Burlington.”

“How? They cut off the coaches since David did his beatdown and run.”

“Okay!” Janelle said. “I’m ready to start.”

Vi came over and sat next to Nate and Stevie. Nate looked at Stevie anxiously, but Stevie turned her attention straight ahead.

“Okay,” Janelle said, nervously knotting her hands together. “So I’m going to do my speech and then I’ll run the machine. So. Here we go. The point of engineering is to make something complex into something simple. The point of a Rube Goldberg machine is to make something simple into something complex . . .”

“Why?” Nate said.

“For fun,” Janelle replied. “Because you can. Don’t interrupt. I have to do this. The point of engineering is to make something complex into something simple. The point of a Rube Goldberg machine is to make something simple into something complex. The Rube Goldberg machine started as a comic. Rube Goldberg was a cartoonist who was also an engineer. He created a character called Professor Butts . . . someone’s going to laugh at that, right?”

Vi gave a thumbs-up.

“Okay, I’ll pause for laughter. A character called Professor Butts, who made ridiculous machines to do things like wipe his mouth with a napkin. People liked the comics so much that Rube Goldberg machines became a feature in his comics and then, later, a regular competition. . . .”

Stevie’s mind was already drifting. Was this what murder was? Something simple that became complex?

“. . . the dimensions cannot exceed ten feet by ten feet and can use only one hydraulic . . .”

Who put that message on the wall? What was the point of it? Just to mess with her? If Hayes or David had done it and Ellie knew about it, why hadn’t she told Stevie?

“. . . and this year’s challenge is to break an egg.”

Janelle delicately placed an egg in a small egg cup on a table by the far wall where a white plastic sheet had been strung up.

“So,” Janelle said, returning to the front of the long and winding machine. “Here we go!”

She depressed the lever on one of the toasters, and it popped up a second later, shooting out a piece of plastic bread. This tipped a wooden lever above, which sent a little metal ball rolling down a series of small half-pipes attached to a menu board. The ball kept rolling, continuing over a tray in the hand of a chef figurine. It fell from there, plopping into a bowl on one side of a scale. This raised the opposite side, which triggered the release of another ball.

The machine made so much sense. A seemingly pointless trigger set off the series of events. The ball rolled, knocking each strange little piece into play. Hayes making a video about the Ellingham case. Janelle’s pass being stolen to get the dry ice. The message on the wall. Hayes turning at the last moment on the day they were shooting, saying he had to go back for a minute to do something and never coming back again. Stevie realizing that Ellie had written the show. Ellie running into the walls, then getting into the tunnel and never coming out.

Another ball was triggered, running down the rims of a stack of cups, which tumbled into the soda dispenser. This began pouring liquid into three plastic pitchers. These weighed something down and . . .

Stevie blinked into alertness as three paintball guns fired off at the same time, all pointing at the egg, which exploded in a blast of red, blue, yellow, and albumen.

Vi screamed in delight and jumped up to embrace Janelle.

“That was pretty good,” Nate said.

Stevie nodded absently. Of course, she had missed the event that triggered the gun. She was looking right at something but she couldn’t see it. Where do you look for someone who’s never really there. . . .

At some point, the gun placed in act one goes off, usually in the third act.

That was one of the most important parts of being a detective: keep your eye on the gun.

April 4, 1936

DOTTIE EPSTEIN DID NOT MEAN TO START WATCHING FRANCIS AND Eddie that day. She had been minding her business up in the high crook of a tree, bundled in a big brown sweater knitted for her by her aunt Gilda, a book open on her leg. The April weather meant that it was not warm, but the mountain was no longer frozen. You could be free in the space again, and it was good to be in the woods, out in the air. The tree was a perfect place to read, to spend some time with Jason and the Argonauts.

That’s where she happened to be, quiet and out of sight, when Francis and Eddie came by. They were close, tight, their heads almost together as they walked. (How did people walk like that, heads so close? It was fascinating to see, like something from the circus.) And there was something in the way they were walking—silent, smiling, quickly but not fast. It was a walk that suggested they did not want to be noticed.

Unlike the other rich girls, Francis was nice to Dottie. She wasn’t like Gertie van Coevorden, who looked at Dottie like she was a walking bag of rags, her eyes lingering on every patch in her clothes. (Dottie’s mother had worked so hard on sewing those patches in her coat. “Look, Dot, you can barely see the stitches! Look how good this thread matches up. I got it at Woolworth. Isn’t that a good match? I spent all night on it.”) Gertie unpicked Dottie’s mother’s seams, judging her whole family, her entire reason for being in one sweeping glance of her small, blue eyes. “Oh dear, Dottie!” she would say. “You must be so cold in that thing. Wool isn’t quite as warm as fur. I have an old one I can lend you.”

It might have been different if Gertie had actually lent her the fur. But that was part of it. They mentioned things, and they forgot. It was a tease.

Francis, however, was the real kind of nice—she left Dottie alone. That was all Dottie really wanted. When they did talk, which wasn’t often, it was about something good, like detective stories. Francis loved to read, almost as much as Dottie did, and her passion was crime. That was, in Dottie’s opinion, a noble interest. Francis also liked to sneak about. Dottie heard her moving around at night and would peek out her door to see Francis creeping down the hall, or sometimes going out the window.

It was this quality that caused Dottie to slip out of the tree, almost automatically, and loosely trail them. Perhaps, she thought, it was because of her uncle the policeman. “Sometimes, Dot,” he said, “you just know. Follow your instincts.”

Francis and Eddie went back, to the raw, wild part of the grounds, where thick tree cover was cut through with only the roughest paths. They wended back to the place where the rocks were still being worked off the face of the mountain. There were massive piles of stone, some of which looked like it was in the process of being broken down into smaller pieces for building materials. The path was extremely uneven, cutting up sharply. Dottie followed, as silently as she could, using the trees to pull herself up the rocky steps. Francis and Eddie were two flashes of color in the landscape, and then—they were gone.

Just like that. Gone. Gone in the trees and the rock and the brush.

Clearly, they had disappeared into one of Mr. Ellingham’s little hidey-holes, one Dottie herself had not yet found. She was filled with fear of discovery and the thrill of the mystery in equal measure. She considered going back to her reading spot, but she knew she would not be able to do it. So she backed up a few steps, to a point she knew they could not have vanished into, and tucked herself behind a tree.

She waited there for over two hours. She had actually gotten back into her book when she heard the crunch of their steps and ducked down just in time. They came out, whispering, laughing, hurrying. Francis had a book under her arm.

“Oh God, we’re so late,” Dottie heard Francis say.