Don't miss a thing by getting the latest from the Manchester Evening News sent direct to your inbox GCHQ has created its 'hardest puzzle ever' in honour of Alan Turing appearing on the new £50 note.
But can you solve it? Officials say their new treasure hunt involving 12 puzzles 'might even have left Turing scratching his head'.
The Bank of England revealed the note’s design on Thursday, featuring the pioneering mathematician, who led a Manchester University team that produced Britain’s first general-purpose stored programme computer.
Mr Turing was also hugely instrumental in breaking the German Naval Enigma cipher in 1942, at Bletchley Park – GCHQ’s wartime home.
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