A: You know, I notice that I don't have a knife here. But, you know, I think inside here...
B: Oh my, gosh.
A: There we are. I can use this. This'll be much better.
B: How did you do that?
A: Sure. Here, let me explain it. This is a really cool trick that you can do to impress your friends. First of all, before the trick starts there's a secret setup, and you won't be able to do this right now, but you take the knife and put it in your sleeve. You can do that when no one's looking, especially the restaurant staff.All you do is when you take the roll and you show it, your left hand drops down and the knife comes right here, in the ready position.
You take the bread roll and you push it against the knife, so it pokes through the middle. Then you take these two fingers, and you dig into the center of the bread roll, until you find the tip of the knife and you start to pull it out. And what they don't see is that you're slowly pulling it out of your sleeve, and then once it clears your sleeve, you can bring your hands further away and you pull it all the way through. And that's how you make a knife appear from a bread roll.