Well, that's kind of obvious at the end of the trick eh?
That double blank had to get there somehow!
So, is your question rhetorical? (psst...that's rhetorical)
Anyway, another gimmick, along with a handling technique, is involved.
Also, only press the 'ask question' button once...not 3x as you did. I assure you, your question will post after the first click.
Patience!