Led Zeppelin became famous for it. So too did AC/DC, and apparently even Jay-Z.

It's called “Satanic backmasking” – the embedding of secret messages into music lyrics.

Insulted in his own paper: Rupert Murdoch. Credit:Bloomberg

Now it seems that something similar is going on in the kids' pages of Rupert Murdoch's Sunday Telegraph.

Eagle-eyed readers of last weekend's newspaper may have spotted an unusual assemblage of letters in Harry the Dog's regular word puzzle.