So, I recently looked in the attic at my house and found all my old Magic Tree House books. These books are literally what got me into reading. I'm serious. I remember in, like, kindergarten being so proud because I could read chapter books. Then I decided to do a crossover with the Percy Jackson books, because there was the book, Hour of the Olympics that had to do with Ancient Greece.

Disclaimer: I do not own the Magic Tree House series or the Percy Jackson books.

One sunny summer day, Percy and Annabeth were riding the train from Pittsburg to New York, when it broke down in the middle of nowhere. Well, not quite in the middle of nowhere. They were about a mile from the small town of Frog Creek, or so the driver had told them. They, along with the rest of the train's passengers, walked the mile to the town where they had been told to wait for another train that would come in about two hours. At least it was a nice day.

Meanwhile, two kids named Jack and Annie were planning their next trip to their magic tree house, a secret they had kept for a few months. Their most recent adventure with it? Ancient Greece. It had been 3 days since they got back, with no message from Morgan.

Percy didn't mind the walk to the nearest town, because he was with Annabeth. It had been 10 months or so since the Giant War had ended. They were walking though a wheat field. On days like these, Percy could almost forget Tartarus, about all they had been through and all that was yet to come. He thought about their trip to Pittsburgh. They had been visiting Grover, who was posing at a school looking out for demigods. They had stayed for one night, and now were headed back to camp.

Soon they reached the town. Frog Creek was a nice place, a small town that was cutesy and touristy almost. He and Annabeth found a nice place for lunch, a small café near the town center, then went for a walk in the Frog Creek woods to pass the time.

They came across an oak tree, one of the tallest around it seemed, with a little tree house perched between two branches at the top.

"Want to climb it?" Percy asked, half-jokingly.

"Sure. Why not?" Annabeth said.

She went up first.

"Whoever owns this tree house must have just been here, 'cause there are a ton of books that don't seem to be damaged by the weather. Kinda strange," Annabeth called down.

Percy climbed the rope ladder. The house was filled with research books, the kind elementary school kids used in school for projects. On the floor, a giant letter M was painted.

Annabeth picked up a book about Ancient Greece. It had been left open on the floor.

"Someone likes Ancient Greece, it would seem," she commented.

"And Rome," Percy added, picking up another book.

"And China," Annabeth continued, finding yet another.

She held up the Ancient Greece book. Outside, they could hear some kids. They seemed to be climbing the rope ladder.

"We'll explain when they get up here," Annabeth said. She looked at the book again. "Don't you ever wish we could go there, back in time?" she said, pointing to a picture.

The tree house started spinning. It spun faster and faster until everything was still.

Absolutely still.