They went out of the room. Fatty heard the key turn in the lock. He was a prisoner. He stared gloomily at the shut door. It was his own fault that he was in this fix. But he wasn’t going to get the others into it too - no, not even if those men beat him black and blue!
The Secret Message
Fatty heard the footsteps of the men clattering down the uncarpeted stairs. He heard the front door close quietly. He heard the sound of a car starting up. The men had gone.
He tried the door. It was locked all right. He went to the window. It was pitch-dark outside. He opened the window and felt the bars. They were too close together for him to slip out between them. He was indeed a prisoner.
He went and sat down again, shivering. Fright and the winter’s chill made him shake all over. He saw the electric fire and decided to put it on. He might as well be warm, anyway!
He sat down once more and gazed gloomily at the sheet of notepaper. What a bad detective he was, to allow himself to be caught like this! It was terribly careless. The others would never admire him again.
“Well, I shan’t write that letter, anyway,” thought the boy, but he trembled to think what his punishment might be if he didn’t.
Then an idea came to him. It was really brilliant. He sat and thought about it for a while. Yes - it would work if only the others were bright enough to catch on to the idea too!
“I’ll write an invisible letter on this sheet of paper, and I’ll write a letter in ink on it as well!” thought Fatty. “I bet Pip and the others will think of testing it for secret writing. Golly - what an idea this is! To write two letters on one sheet, one seen and the other unseen! I bet the men will never think of that!”
He looked at the sheet of paper. It was faintly ruled with lines. He could write his secret letter between the lines and the other letter on the lines! When the others tested it for secret writing, they would then be able to read his real letter easily.