Only the sharpest minds succeed: UK spy agency asks Brits to crack secret code

Apr 23, 2021
Top UK intelligence agencies have joined Instagram with the aim of recruiting a new generation of spies. Source: Instagram/@gchq

Martinis, fast cars and pretty ladies … If the life of a spy sounds thrilling to you then this mysterious coded maths puzzle will be right up your alley.

The UK’s Government Communications Headquarters (GCHQ) shared a coded message on its Instagram story on Friday, calling on the world’s best and brightest to crack the puzzle for a chance at glory.

The GCHQ, which is the UK’s intelligence, cyber and security agency responsible for providing signals intelligence and information to the government and armed forces, only gave people 24 hours to solve the code, meaning followers had to put on their thinking caps and knuckle down before it disappeared from Instagram.

The image, to most folks, appears to be a series of random letters and numbers in sets of two and was simply captioned by the agency: “Decode the message.” Underneath the coded message, for the few of us willing to even hazard a guess, there is an empty box to send the organisation your answer.

Luckily, for those of us who want to know the answer without doing the work – the agency has that covered.


If you’re still trying to work it out, then stop scrolling now.

The agency revealed just five hours later that the coded message was written in the hexadecimal numeral system, a numeral system made up of 16 symbols as opposed to the decimal system which uses 10. Hexadecimal uses the decimal numbers and six extra symbols.

The answer to the message was the announcement that spy agency MI5 had also joined the social media platform, and read: MI5 joins Instagram.

However, over on the M15’s new Instagram things were just as mysterious. The spy agency’s first post was a glimpse inside MI5’s top secret headquarters, Thames House on London’s Millbank. Taken from a worm’s-eye view perspective, the pic took many a little while to figure out which end was up and which was down.


View this post on Instagram


A post shared by MI5 (@mi5official)

MI5 captioned the post: “The secret to successful spying? Consider all angles. It’ll give you a better view … This is the view our staff see as they enter MI5 HQ in Thames House, London. Behind these pods lie some of the UK’s best kept secrets. Follow us as we open our doors to Instagram, granting you exclusive views of life inside MI5.”

The new Instagram page @mi5official, comes as the agency’s youngest-ever boss, Director General Ken McCallum gave the green light to set up the account in a bid to drive recruitment among millennials and to rid the organisation of its “martini-drinking stereotypes”.

Only spies, government officials and a handful of visitors have ever set foot inside the building, making this picture the first time in 112 years that the public has been given the chance to sneak a peek inside M15.

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