In Mary's case, Elizabeth's master code breaker Thomas Phelippes cracked the cipher and exposed her crime.

FORBES: I've got a secret

Policyholders might not know what they are entitled to, since it often feels as if you need a code-breaker to decipher disability insurance contracts.

WSJ: Conquering Retirement: Uncovering Hidden Disability Benefits

Last year he launched a petition on the No 10 website calling on the government to make a posthumous apology to World War II code-breaker and computer pioneer Alan Turing for his treatment by the authorities for being gay.

BBC: Campaign builds to construct Babbage Analytical Engine