In 2006 a couple from Erba, Italy, murdered four neighbors. An encrypted letter from this criminal case is still waiting to be solved.


“Fringe”, a successful US TV series, contains a hidden code. It has been solved by fans of the series.


The Zodiac Killer has hit the cinemas again. In a new film titled “Awakening the Zodiac” the code of the killer is broken.


A reader from the Philippines has asked me for help. Can somebody solve the crypto puzzle he is currently working on?


In 1944 a member of Hitler’s paramilitary organization SS sent an encrypted radio message to a recipient named Lippert. The cleartext is unknown.


Bruno Borges, a Brazilian student who has mysteriously vanished from his home, left behind several encrypted books. A publishing company has now published one of them. It has entered the Brazilian bestseller list.


The Dorabella Cipher is one of the most popular crypto mysteries in the world. 120 years after its creation still nobody has found the solution.


A few years ago I took pictures of a rare encryption device from the Cold War era. Can a reader help to find out more about it?