Say what?

A young woman came into the bookshop and asked for 'Annie's spectacles'. I repeated it, she repeated it again, I typed it into the computer, nothing came up. I assumed from the title that it was a children's book, but I asked the customer, just to be sure.

"No, it's a play," she said.

I hadn't heard of it, but hey ho. I checked a different search engine. Nothing.

"Annie's spectacles?" I said again.

"It's very famous," she said.

I shook my head. 

"Nothing's coming up."

Then suddenly, penny drops, ahh, "An Inspector Calls".