The Knock-Knock Man.
I'm the Knock-Knock Man.
When you're upset I can lend a hand,
cause the Knock-Knock Man is who I am.

When your luck's gone down,
and got you feelin' blue,
I'll say "Knock-Knock."
and you say, "Who?"
You'll get the joke once you understand,
no one ever laugh's with the
Knock-Knock Man.