Every time my neighbor Stan says “That’s the oldest trick in the book!” I ask him “Which book?”
“Well, it’s just an expression!” Stan says. “Don’t be so literal!”
As a collector of books, I own many volumes of tricks, and the oldest trick in the oldest book involves magically turning a person into a frog.
Sadly, the first page is missing from that oldest volume, so there may be an even earlier trick, but it’s lost to history.
I show the book to Stan. “See,” I say. “This is the oldest trick.”
“Ribbit,” says Stan, and he hops away.