Investigate with TKKG in a new, exciting case that you do not know from the radio plays or books! Stalked! Gaby feels a shiver down her spine: At the end of a Spanish class at the adult education center, she discovers an anonymous letter between the pages of her book. A stranger who signs "Your faithful prince" seems to be constantly watching her and trying to intimidate her. Tim, Karl, Klößchen and Gaby take up the pursuit of the stranger. The clues soon lead them into the world of the Internet, webcam spying and chat rooms Just when the young detectives think they are on the right track, the case takes a dramatic turn. Will TKKG win the hunt for the "prince" across the city?