The Bletchley Circle Review – 1943 codebreakers

(c) World Productions/ITV

It’s 1943 at Bletchley Park, the covert code-breaking operation nestled in the quiet Buckinghamshire countryside. Four women code-breaker are conferring. Susan is showing her colleagues the pattern she has seen in the reams of German data – has she spotted a code? She takes it straight to the top, as her colleagues wait anxiously to hear some news. Susan returns – she is right and the British troops now know where the next German battle is going to take place.

This is the starting point of ITV’s much anticipated crime drama, The Bletchley Circle. The 1943 code-breaking scene creates a unique and fascinating back story for the main characters in the drama (as shown left to right on the picture):

Millie (Rachael Stirling) – aristocratic, streetwise and glamorous, Millie has specialist map reading skills.

Susan (Anna Maxwell Martin) – conventional, cold with an extraordinary ability to see mathematical patterns.

Lucy (Sophie Rundle) – the youngest member of the circle, Lucy is young, naive and has an exceptional photographic memory.

Jean (Julie Graham) – the eldest of the four, she is a methodical and stern organiser who is in charge of the group at Bletchley.

This first scene provides us with the skills and characteristics that the women later rely on to solve a murder in 1952, where the main focus of the drama is based. It also alludes to a theme relevant for the era; how do the women adapt from their independence and sense of purpose during the war to their less dramatic, more traditional lives in post war Britain?

In the episode summary, ITV doesn’t reveal exactly where the women worked as code-breakers at Bletchley Park, other than they are ‘inside one of the machine huts’.  I wonder if the show will use the opportunity to add real fact about a chosen Hut and the type of work undertaken there? Equally the writers may prefer to keep the scene as a generalisation, thereby the factual waters are not muddied with the dramatic fictional setting?

In the TV Times article by Susan Selwood, she states ‘The makers are keen to stress that the characters are not based on real women who worked at Bletchley but are inspired by them.’ It will be interesting to see if the same is true for the actual facts of working in one of the Huts. For instance, both Hut 6 and Hut 8 had machine rooms.

Hut 6 was the centre of operations to break the Enigma cyphers used by the German Army and Air Force. It was possibly the busiest hut of all, dealing as it did with two sections of the German military machine.

Hut 8 was allocated to the team, led by Alan Turing and chess grand master Hugh O’Donell Alexander, that attacked the Naval Enigma keys used by the German U-boat and surface fleets. It was to this team that an Enigma code book, captured from U-boat 110 in May 1941, was duly delivered, helping greatly in the breaking of the Naval Enigma. The naval codebreakers provided vital day-to-day intelligence in the desperate battles between the Allied convoys and the U-boats determined to cut Britain’s lifeline across the Atlantic.

Codebreaking in Huts 6 and 8 was organised into the following sections:

  • Registration Room – traffic analysis
  • Intercept Control Room – liaison with intercept stations
  • Machine Room – finding cribs, generating menus, and finding the keys
  • Decoding Room – decyphering the messages
Quoted from Bletchley Park Museum website page about Huts 6 & 8

Cribs were effectively calculated guesses about the most likely plain text of a message. For instance, common phrases, like ‘nothing to report’, or subject matter like weather reports or information from  identical messages sent to the two different naval cipher machines used by the German Navy warning of mines at sea, gave code-breakers a useful starting point from which to break the cipher. These would be the sort of patterns Susan would have been looking for as she analysed her message at the start of the episode.

All too soon we leave the war and move forward nine years to May 1952, where Susan finds another pattern in a string of London murders. Her first attempt at decoding the patterns fail but she soon convinces her Bletchley colleagues to join the hunt for the killer and save the fifth victim.

Although the drama is only briefly based at Bletchley Park during the war, I think the idea is a unique starting point for a crime drama that has a strong basis to drive the story forward and gives the characters real depth.

I will be watching The Bletchley Circle with much enthusiasm. I can appreciate it for the fictional enjoyment and appreciate that it will highlight the work of women code-breakers during World War 2, of which there were very few.

In later posts I will review each episode of The Bletchley Circle, discuss the real women code-breakers, and also consider whether historical fiction has a duty to accurately represent the facts.

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