Great news for those who love cryptologic challenges! The new edition of the CODEBREAKERS is online. The contest is dedicated to Marian Rejewski, Jerzy Rózycki, and Henryk Zygalski, the three Polish codebreakers who were in 1932 the first to break the encryption of de German Enigma cipher machine.

The contest website features lectures where you can learn more about the history of cryptography, different codes, and of course the tasks and codes. There are three levels, each with its own starting date, and the website is now available in nine languages.

You can already register and play the single-players trial level, and to participate in the contest, you register a team in the levels you want solve, and you can invite two more players for a three-person team. Each level consists of several stages, each with lectures and tasks to solve. The BASIC level game with tasks in English will start soon.

Make sure to be prepared and registered in time for the start of the competition:

• TRIAL Currently open!
• BASIC 21 October
• ADVENTURE 15 November
• ENIGMA 29 November

Visit theCODEBREAKERS website for more information and follow their Facebook page to catch the latest news. You can also promote their website and contest by sharing their poster and flyer. See also the Codebreakers introduction video below.

Software developer Craig Longhurst has always had a keen interest in all things technical. In 2002 he got the idea of building a working Enigma, the well-known German cipher machine of which various civil and military versions were produced from 1923 throughout the Second World War.

Craig decided to build the famous Enigma I but designing the rotors with their internal wiring and contacts proved complex. Over the years, he learned laser cutting for the rotor contact holes and later 3D printing for the discs. These were only a few of the many obstacles that required quite a bit of work and imagination, not only to construct the electrical parts, but also various mechanical components, all made with Meccano parts.

Although he considered the rotors the most difficult part, it would be quite an understatement to call the Meccano construction of the Enigma, the keyboard with numerous switches, the contacts and lamp panel "easy". The result of his creativity was a fully working Meccano Enigma I in 2024.

Craig's Enigma is published in the Constructor Quarterly issue No 145 and if you're interested in Enigma and Meccano, you're in for a real treat. The issue has 16 pages on his Enigma, with 26 excellent highly detailed photos from all parts, accompanied by information about the development and construction. Available as back issue, sent all over the world. In the video you get an idea of how complex Craig's project was, and why it took 22 years to complete his award-winning Enigma.

When George Lasry, Norbert Biermann and Satoshi Tomokiyo started deciphering more than fifty letters they found in the Bibliothèque Nationale de France, they unexpectedly discovered that these were letters presumed lost, written by the imprisoned Mary, Queen of Scots (1542-1587, painting circa 1559).

In 1567, Mary Stuart was forced to abdicate, and imprisoned in the Scottish Lochleven castle, but escaped the next year to England. Since Mary had a claim to the English throne, she was a threat to her cousin, Queen Elizabeth I, who kept her captive in England. Still, Mary remained involved in plots to take the throne.

In 1586, Anthony Babington, the leader of a plot to assassinate Queen Elizabeth, established a secret communications channel for Mary Stuart. However, Sir Francis Walsingham, secretary and spymaster of Elizabeth, had placed several spies in Mary's circle, compromising the Babington plot. When Mary did not object to the assassination of Elizabeth in a letter to Babington, she sealed her fate. Her conspirators were executed in September 1586 and Mary Stuart, 44 years old, followed on 8 February 1587.

Mary was known to correspond with here allies though encrypted letters, but many of those were believed to have been lost. Most of the recently discovered letters were addressed to Michel de Castelnau, the French ambassador to Londen. Although they are 445 years old, deciphering them still proved to be a complex task for the codebreakers. The team later found plaintext versions of some of those letters in the British Archives, leaked to Walsingham by a mole in the French embassy. These confirmed the correct deciphering of some messages from the Bibliothèque Nationale de France.

A fascinating story of deceit and treason, uncovered by the three talented codebreakers in 2023. Their codebreaking achievement is published in detail on Cryptologia. On the Cryptiana website are the ciphers of Mary, Queen of Scots, the discovery and codebreaking of 50+ letters, and simulated paper-and-pencil codebreaking of a ciphered letter. See also the DECRYPT project.

Below the excellent talk by George Lasry, explaining in detail how they deciphered the messages, and to understand the animosities between Mary and Elizabeth, watch the BBC documentary.