“What’s he looking at?” Chelsea asks. She turns to Mr. C for an answer, but his face has gone pale. All of a sudden she knows the truth. They’re still back in time! Her eyes go wide. “The twin towers are still here, aren’t they?”

The others gasp. Jamal sits down hard on the ground. Maya bursts into tears. Chelsea puts her arm around her and they hug each other. All the other places they visited were events that happened so long ago in history. But the attack on the twin towers on September 11th happened right before they were born. The ripples from it are still very much playing out all across America—and the world.

The kids start talking at once. “We have to warn the mayor! We have to stop this!”

Chelsea’s heart sinks. She knows how this goes by now. They all do, and nothing they’ve done has changed anything. But they have to try!

From his perch in the tree Cooper shouts, “Mr. Mayor! Mr. Mayor! You have to listen to us! Please!” But his voice is drowned out by the crowd, and he’s hidden from view by all the umbrellas. Mr. C is frozen in place, but the rest of them rush to the stage. They only make it a few feet before everything fades around them. “Nooooo!” they shout in defeat and frustration.

When the new scene solidifies around them, they gasp in shock. The new Imagination Tree they see now is nothing more than a splintered stick in the ground. They’re on a hilltop looking over the ruins of a small town. Nothing is standing as far as their eyes can see and there’s an eerie buzzing in the air, like some sort of broken technology. This doesn’t feel like anything they’ve learned about in history.

They all shudder and move closer to Mr. C who is suddenly alert and wide-eyed. “I think I finally understand,” he announces. “what this trip has been about….”