01What happened

The story, straight

A collection of documents detailing Alan Turing's top-secret 'Delilah' project — a voice-encryption machine he built during World War II — was recently sold at auction for almost half a million dollars. The IEEE Spectrum report draws on Turing's own notebooks to reconstruct the project, which ran from roughly 1943 to 1945 and produced a working portable voice scrambler. Turing led the work alongside his assistant Donald Bayley in a secret electronics laboratory in the English countryside, while simultaneously making regular bicycle trips to Bletchley Park to continue his codebreaking work. Bayley, a young electrical engineer, reportedly knew little about his boss's other life breaking German codes. The pair celebrated VE Day on 8 May 1945 with a quiet walk together.

alan turing built a secret voice-encryption machine called 'Delilah' during WWII, and the notebooks documenting it just sold at auction for almost half a million dollars. the IEEE Spectrum piece pulls from turing's own handwritten notes to reconstruct the project — he ran it from a secret countryside lab with assistant donald bayley while still biking to bletchley park on the side to break german codes. bayley apparently had no idea what turing was really up to. the two celebrated VE day with a quiet walk.

02Spread timeline

Where it actually started

~1943-1945Origin
Turing and assistant Donald Bayley develop the Delilah voice-encryption machine in a secret countryside lab.turing and bayley build the delilah voice scrambler in a secret countryside lab
source
8 May 1945
Turing and Bayley celebrate VE Day with a long walk after completing the Delilah project.turing and bayley celebrate VE day with a walk — project basically done
source
Jun 2026
Turing's Delilah notebooks sold at auction for almost $500K; IEEE Spectrum publishes a deep-dive into the project.notebooks sell at auction for almost $500K, IEEE spectrum publishes the deep-dive
source

03Source receipts

Every claim, linked

04What's solid, what isn't

What's solid and what isn't

Confirmed
  • Alan Turing led a top-secret voice-encryption project called 'Delilah' during WWII.
  • Turing worked alongside assistant Donald Bayley in a secret countryside electronics lab.
  • The Delilah project notebooks were recently sold at auction for almost $500K.
  • IEEE Spectrum published a detailed reconstruction of the project based on Turing's own documents.
Disputed
  • The exact auction house and final sale price (the source says 'almost half a million dollars' but does not give a precise figure).
  • The full extent of the Delilah machine's operational use, if any, beyond the prototype stage.

05Why it matters

The editorial take

The Delilah project is one of the least-known chapters of Turing's wartime work, overshadowed by his more famous contributions to breaking the Enigma and Lorenz ciphers. The auction sale and subsequent IEEE deep-dive bring new primary-source material into public view for the first time, filling a significant gap in computing and cryptographic history. The story also illustrates Turing's DIY engineering approach — he built much of the equipment himself rather than delegating — which contrasts with the institutional image of wartime codebreaking.

this is the turing project almost nobody talks about — enigma gets all the attention, but delilah shows he was also building portable voice scramblers from scratch. the fact that his own notebooks went for almost $500K at auction tells you how hungry collectors are for primary-source turing material. good reminder that the guy was biking between two secret labs simultaneously.