Knock, knock. Who's there? Me.
Knock Knock Me
Explanation
Explain Bear
Okay, so, you got this "knock knock" thing, right? Someone says, "Knock knock." Then you gotta ask, "Who's there?" And the dumb-dumb at the other end is supposed to say a name. But this guy? He just says, "Me." It's like he doesn't even know how jokes work. You probably do the same thing, you dummy.