Books in the Showcase

The digital Escape Room

You look through the books and coincidentally find a marked page.

The Caesar cipher is a simple monoalphabetic substitution encryption that has been used for over 2000 years. The encryption is based on cyclical displacement, e.g., the displacement of a letter by a certain amount to the right or left. In ancient Rome, encryption disks with two movable components each labeled with the alphabet were used to encrypt or decrypt a message.

In the original Caesar encryption, which was shifted 3 letters to the right, Caesar is encrypted as follows: “Fdhvdu”.

Find out, how much the disk was shifted from the original text.

You can download the text here, to be able to work better.

Here is a hint: The letter “e” is the most common letter in the unencrypted text. The letters “a” and “t” are also represented frequently. Additionally, double letters such as “tt” can be found as well.

NhpBz PBspBz Jhlzhy pz vul vm Aol tvzA mhtvBz nlulyhsz vm huApxBpAF, Dov mvBnoA opz DhF Av Aol Avw vm Aol Yvthu zAhAl AoyvBno opz tpspAhyF zrpssz. Opz hktpupzAyhApCl jhylly zvvu AByulk puAv h tpspAhyF vul. Ol Dhz wvzAlk Av DohA pz uvD Aol Ihsrhuz, uvyAolyu PAhsF huk Myhujl. aolyl ol wyvClk Av il h zBjjlzzmBs WyvjvuzBs, Dopjo jvyylzwvukz Av h tpspAhyF nvClyutluA vmmpjphs. HmAly opz nsvypvBz jhtwhpnuz, Jhlzhy pupAphAlk h jpCps Dhy pu Dopjo ol wylChpslk hnhpuzA opz wylCpvBz hssF WvtwlF. Ol Dhz Aolu thkl h spmlsvun kpjAhAvy. H whysphtluAhyF nyvBw pu Aol ZluhAl Dov ilsplClk AohA khyr Aptlz Dlyl vu Aol ovypGvu AoyvBno opz hwwvpuAtluA hz kpjAhAvy tByklylk opt DpAo ADluAF-Aoyll zAhi DvBukz pu Aol ZluhAl. Jvsvy iBAAvu uBtily mpCl ishjr.

Hint Encryption

Read the text and find out which letter appears the most, this is probably the encrypted “e”. Adapt the decryption disk to “e”. This way you’ll decrypt the other letters as well. The last sentence is the most important.

Are you still stuck here? Send us an email to icse.escaperoom@ph-freiburg.de, we’ll help you as quickly as possible.