From "Whodunit"

When something strange happens, and no one knows why
You need a great detective, and I’m that guy
When someone did a crime, but you don’t know who
You call a great detective to find out who for you
Who solves the mysteries? Who finds out?
Me, the great detective! And when I do I shout
Aha! When I find a clue
Aha! That’s just what I do
Aha! That’s the word I yell
Yes, I’m the great detective, and here’s how you can tell, aha!
Got a mystery on your hands? On your feet or on your head?
Well, don’t just stand there, call me instead
With my great detective hat, and my great detective mind,
And my magnifying glass, there’s no answer I can’t find
The why, the what, the when, where, who
I’ll answer every riddle, I’ll follow every clue
Aha! That’s just what I’ll say
Aha! When I’ve saved the day
Aha! In a British voice
You need a great detective, I’m your number one choice
Aha! Aha! Aha! Ahaaaaaa!