Jack and Annie pressed through the crowd of people swarming about the Hall of Machines. Finally they reached the exit and slipped back out into the warm Paris night. The fair was just as crowded outside the hall as inside. Musicians played guitars, singers sang, food sellers shouted, “Chocolate milk! Cheese! Bread! Wine!”

“We have to get to the Pasteur Institute fast!” Annie shouted to Jack.

Jack pulled out their guide book and scanned the index, looking for the Pasteur Institute. “It’s not in here,” he said. He closed the guide book. “It must not be part of the fair.”

“Maybe one of those horse-and-buggies can take us there,” said Annie. She pointed to a row of carriages along a street. There was a line of people waiting to get into them.

“Come on!” said Jack.

Annie and Jack made their way through the crowd and stood in the carriage line.

“Thomas Alva Edison and Alexander Graham Bell!” said Jack. “The sorcerer must think they’re new magicians with secret powers!”

“And now he’s invited them to some kind of party,” said Annie, “so he can steal their secrets.”

“I’ll bet he’s inviting the other two,” said Jack, “the Magician of Iron and the Magician of the Invisible.”

“I wonder if they’re inventors, too,” said Annie.

“Come on, it’s our turn,” said Jack.

They had reached the front of the carriage line. “We need to go to a place called the Pasteur Institute,” Jack called to the coachman. “Can you take us?”

“But of course,” said the man.

“Thanks!” said Annie. She and Jack climbed into the back of the open carriage. The coachman shook the reins, and his white horse clopped down the cobblestone street.

“Excuse me,” Annie said, leaning forward. “But what exactly is the Pasteur Institute?”

“It is a laboratory for finding the cures for diseases,” said the coachman.

“Oh …,” said Annie. “Interesting.” She turned back to Jack. “Why would an evil sorcerer look for magicians in a place like that?”

“I don’t know,” said Jack.

“Maybe the sorcerer got sick,” said Annie.

“I don’t think so,” said Jack. “But now we really need a plan. What if we run into him at the institute? Remember, he has magic powers.”

“But we have magic powers, too,” said Annie.

“Right,” breathed Jack. He reached into his satchel and pulled out their book:

10 MAGIC RHYMES FOR ANNIE AND JACK
FROM TEDDY AND KATHLEEN

By the light of the carriage lantern, Jack and Annie looked at the table of contents.

“Remember, we can only use a rhyme once,” Jack said to Annie. “Make a Stone Come Alive— we’ve done that. Make Helpers Appear out of Nowhere—done that. Mend What Cannot Be Mended—done that.”

“But we haven’t used Spin into the Air.” said Annie, “or Make Something Disappear, or Find a Treasure You Must Never Lose, or Pull a Cloud from the Sky, or Turn into Ducks.”

“Go back, go back,” said Jack. “Make Something Disappear. What about that?”

“Is a person a ‘something’?” asked Annie.

“Why not?” said Jack. “This one rhyme could solve our whole problem. We’ll just make the sorcerer disappear.”

“Yes,” breathed Annie.

“Okay, here’s the plan,” said Jack. “Let’s memorize the rhyme now. Then as soon as we see the sorcerer, we can say it without having to look in the book.”

“Great,” said Annie.

Jack turned to a page in the rhyme book. “I’ll memorize the line that Teddy wrote. You memorize the line in Kathleen’s language,” he said.

“Got it,” said Annie. She looked at the rhyme and started to say her line, “Thee-be-wan—”

“No, don’t!” yelped Jack, putting his hand over her mouth. “Don’t say it out loud until we need it! You might accidentally make one of us or something really important disappear!”

“Sorry,” said Annie.

“We’ll practice silently,” said Jack. “And we’ll each only learn our own line. So neither of us can say the whole rhyme at the wrong time.”

“Good plan,” said Annie.

Annie studied her line silently while Jack studied his. As Jack repeated his line in his head, the carriage rolled down a busy street. The street was filled with more carriages and many bicycles. Some of the bikes were built for two people. Couples dressed in fancy evening clothes pedaled together.

Other Parisians ate by candlelight in outdoor cafés. Waiters in white aprons carried trays high in the air. Everyone seemed relaxed and cheerful. As the carriage turned onto a quiet tree-lined street, Jack wished that he and Annie could just have fun in Paris like everyone else and not be worrying about an evil sorcerer.

“Here we are!” said the driver, interrupting Jack’s thoughts. He brought the carriage to a stop. “The Pasteur Institute.”

“This is it?” said Jack. The Pasteur Institute looked like a spooky mansion. Its huge front doors were closed. Its tall windows were dark.

“Are you sure we’ve come to the right place?” Annie asked in a small voice.

“But of course I am sure,” said the coachman. “The institute appears to be closed. Would you like me to take you somewhere else?”

“No thanks,” said Jack. “We’ll get out here.”

Annie gave the coachman a few coins. Then she and Jack climbed out of the carriage.

“Thanks,” said Annie.

The coachman flicked his reins, and the white horse trotted away down the street.

Jack and Annie stared at the dark, silent building.

“I guess we should go up and knock,” said Annie. She and Jack climbed the stone steps to the gigantic front doors.

“We’ve come to the right place,” said Jack. A gas lamp lit a small metal sign that said:

Louis Pasteur Institute

Jack knocked on the door three times.

No one answered.

Annie turned the huge handle and pushed. The door was locked.

“Maybe there’s another door somewhere,” said Annie.

Jack and Annie walked around the institute. They knocked at a back door and a side door, but no one answered.

When they got back to the front of the building, Jack heaved a sigh. “It’s no use,” he said. “We’ve come to a complete dead end.”

“We can’t give up,” said Annie.

“I know,” said Jack. They both stood looking at the street. All was quiet, except for a few bikes rattling by.

Suddenly a whispery voice came from behind them. “Hellooo?”