"Nellie never goes anywhere without her trusty iPod. She's a music fanatic and always knows the latest bands. But could there be another reason she's so attached to her iPod? Amy and Dan have started to get a little suspicious about their au pair. They heard a mysterious message on her phone that made them wonder if Nellie was more than she seemed. There haven't been any more strange voice mails, but could that be because Nellie's found a sneakier way to transmit secret information? Could her playlist actually be a coded message?"