Narrator Mitch Pileggi says, "I've heard all of you viewers' guesses about who the Masked Magician really is --- trust me, you're not even close." This indicates that Mr. Pileggi knows that it's Val Valentino, yet in the next episode he shruggingly states, "Well, don't ask me about the Magician's true identity--- even I'm not in on that secret."
During the stretch illusion, before the reveal you can light appearing between the front door panels as the other assistants enter and exit the box in the rear.