On a Russian website a handwritten notebook from the Soviet era is described. Its content is encrypted. Can a reader solve this unusual cryptogram?


An unknown Freemason author once published a book, the content of which is given as a picture word puzzle (rebus). The solution is not known to me.


A Spanish company has bought the rights to make 898 official replicas of the Voynich manuscript. Another unofficial replica already exists – mine.


Swiss army veteran, Max Rüegger operated an Enigma in Korea in the the 1960s. Here’s his intriguing report.


Russian teenager Vladimir Vinnichevsky (1923-1940) murdered several children and left behind an encrypted note. Can a reader make sense of it?


In 1904, a Bavarian theology student received a postcard written in a shorthand. Can a reader decrypt it?


Albrecht von Wallenstein is one of the most important military leaders in European history. A partially encrypted letter he wrote in 1616 is still unsolved.


In the early 20th century, an unknown person sent three encrypted postcards to a woman in Heidelberg, Germany. Can somebody break these cryptograms?


Henry Debosnys (1836-1883), a convicted murderer, left behind four cryptograms, which  are unsolved to date. Breaking them could shed light on the many mysteries that surround this case.


The British National Archive has published an encrypted letter from the 17th century. The solution is known, but many other encrypted notes of the same kind still wait to be broken.