I Am Your Evil Twin(1998)

R.L. Stine

My double rounded the corner. He was heading for the front doors! He was getting away!

I gritted my teeth and tore around the corner after him.

And suddenly I stood face-to-face with him!

"Who—are—you?" I panted. "Who?"

The boy with my face gave me a mocking smile.

"I'm taking over your life, Monty," he said softly. "And you can't stop me."