Get ready for an epic glow-in-the-dark doodling adventure using the Smiggle Spy Pen! In this video, I tested invisible ink ...

The mysterious image slowly revealed itself to local children. “You draw with white crayon and then you paint over it and it reveals what you drew,” said ten-year-old Rochelle Rakers from Highland.

Some parts of it were what you might call “visibly invisible”: Everyone in Tehran knows about Evin Prison, perched on the ...