For Jonah and his friends, the one sure sign of spring was the opening of the tree house. It had been built in the fork of a huge oak in the Smiths’ backyard. For the past four summers, Sally Smith, Bill Tollbar, Lisa Valdez, and Jonah had convened there almost daily to play games and talk and eat lunch. They used to call it the Oak Tree Club, but now that they were twelve, they were too cool for a club. Although Jonah didn’t want to think of it, this would probably be their last summer before turning the tree house over to Sally’s younger brother and his friends.
On a warm Saturday in late April, Sally got the key from her mother and, with Jonah and the others, climbed the ladder and unlocked the padlock that had kept the clubhouse secure through the long winter months.
The tree house was just one room, with the tree trunk and a large limb poking through the floor and dissecting the space. The structure was solid but far from weatherproof. As the kids unlatched and opened the shutters, they could feel the musty dampness. Anything made of metal, like the telescope stand, was a little rusty, and tiny pools of water near the trunk spoke of last week’s torrential rains.
Jonah and Bill took the job of sweeping it out, while Sally and Lisa did general cleaning. “Oh, my gosh,” said Sally. She was pointing to something on the other side of the room. “Look!”
The boys joined them and saw it, too. There, on the wall, were five words written in blood-red paint: “Welcome Back, Children. — The Specter.”
The Specter was their own creation, a bogeyman they invented last Halloween, right before closing the tree house. Jonah had started the story of an angry tree spirit who seeps through the walls and curses them all. Sally took up the story next, and by the end of the evening, they had managed to scare each other pretty thoroughly.
The four of them stared at the scrawled words, open-mouthed. And then Bill laughed. “Good job, Sal. You had us going there.”
“It wasn’t me,” Sally protested. “I haven’t been up here since we locked up. My mom’s had the key ever since. Go ask her.”
“You probably know where she keeps it,” said Bill.
“I don’t,” said Sally. “I haven’t been up here at all. I swear.”
“Did you guys tell anyone else about the Specter?” asked Jonah. They all shook their heads. “Then it had to be one of us.”
“Right,” said Sally. “One of you guys. You could have sneaked in, probably some day when my family and I were away.”
Bill bristled at the accusation. “And how did we get in without a key?”
“Wait a minute,” said Jonah. “Isn’t there a spare key to the padlock?”
“Right. I hid it inside the tree house. Up there,” Sally said, pointing to the ledge above a window. “Last Halloween, one of you must have taken it, just so you could pull this prank.”
“That’s easy to check,” said Lisa as she hopped up on a chair and brushed her hand over the ledge. A few seconds of brushing and the spare key came falling to the floor.
They all stared at the bright, shiny key. Silently, Sally picked it up and tried it in the padlock. It worked.
Lisa got down from the table, her face white. “So, if Sal didn’t do it, and if the spare key was inside the tree house all along…”
Three of the kids shivered. Could the Specter be for real? But Jonah wasn’t shivering like the others. He was laughing.
WHO WROTE THE MYSTERIOUS MESSAGE?
HOW DID JONAH KNOW?
Sally pointed at Jonah. “Look, he’s laughing. Jonah did it.”
“No,” Jonah protested between chuckles. “Not me. But I know who. Tell ’em, Lisa.”
“Me?” Lisa said. She was scowling, but the scowl erupted into a giggle. “All right, it was me. I took the key last Halloween, just like you said.”
“But the key was on the ledge above the window,” said Bill.
“Nope,” said Lisa. It was in my hand. I dropped it while I was pretending to brush the ledge. You couldn’t tell the difference — except for Jonah.”
“No, you were good,” Jonah, admitted. “I didn’t see a thing.”
“Then how did you know?”
“Because the key was bright and shiny. Everything else in this place is rusty and moldy, As soon as the key hit the floor, I knew it hadn’t spent the winter here.”