But the end didn’t come. When they got to the bottom of the hill they just kept rolling smoothly along, faster now but quieter, with no more breaking branches. Slowly she unclenched her jaw and ungripped the seat. The engine chuffed happily. Cautiously Kate opened her eyes.

They should have been sinking into the swamp by now, with the snapping turtle waiting impatiently to snap the feet off their drowned corpses, but instead they were cruising along easily through dark, still woods.

Kate knew perfectly well that there were no woods here, there was only swamp, and after that an office park, and beyond that the highway. It was impossible.

But the woods didn’t seem to care about that. They just went on getting deeper and darker.

“Where are we?” Tom whispered.

“I don’t know!”

“I can’t believe we’re in a real train!”

“I know, right?”

“I mean what is even happening right now!”

Over the next few minutes Kate and Tom had three separate versions of this conversation, different but all basically the same. They raised the possibility that they were going to Hogwarts and decided they probably weren’t, though that would’ve been cool, too. And it was Kate’s eleventh birthday.

Kate stuck her head out her side of the cab, and Tom stuck his head out his side. She wondered where they were going, and whether it was a good idea to go there, and whether, if they absolutely had to, they could jump out of the train without getting badly injured, and how long it would take them to walk home after that, and how exactly their parents would punish the bejeezus out of them when they got there. They were definitely putting Grace Hopper’s whole permission-versus-forgiveness theory to a serious test.

But at the same time all the excitement, all the energy, all the joy she’d been waiting her whole life to feel were finally thrilling through her whole body. Anything was worth that.

The air outside was getting pretty cold, even though it was June, and Kate shivered in her T-shirt. She was grateful for the warmth of the fire. After a few minutes she saw a pale light through the trees up ahead.

It was dim and distant at first and blinked in and out among the branches, but it got stronger and stronger till at last it came fully into view. It was a train station.

Not a fancy one, just a small country train station, a long lit platform in a clearing among the trees. There were people waiting on it.

Except they weren’t people, they were animals. A few deer, a wolf, several foxes, a big brown bear, some rabbits or hares—or were they the same thing?—and a stripy-faced badger. Perched along a railing at the back of the platform was an assortment of birds, large and small.