watch!

(You) (just) watch!

Inf. Just pay attention to what I do, and you will see that what I said is true! Rachel: I'll get her to change! You just watch! Andy: Good luck! Andy: You watch! You'll see I'm right. Sally: Sure, you are. Bob: Watch! This is the way it's done. Bill: You don't know what you're doing. Bob: Just watch!
References in classic literature ?
You cannot expect me to believe that you have read all this from his old watch