The Government Communications Headquarters (GCHQ) has released a string of "fiendish" puzzles for Christmas, curated by a team of in-house masterminds.
GCHQ is an intelligence and security organisation that provides signals intelligence and information assurance to the government and armed forces of the United Kingdom.
The seven quizzes are featured on their director's Christmas card and are aimed at secondary school teens interested in science, tech and engineering.
GCHQ sends the card to partners in the UK and around the world who work with them to counter threats, including hostile state activity, terror groups and organised crime gangs.
The puzzles are based on the seven disciplines of languages, engineering, codebreaking, analysis, maths, coding and cyber security – critical skills needed within GCHQ.
This year's puzzles come with a twist.
Once six of the seven puzzles have been completed, they must be assembled into three words to form an address. The design on the front helps participants assemble the answers and create three separate what3words locations.
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GCHQ
Director GCHQ Sir Jeremy Fleming said: "From breaking Enigma to harnessing the latest cutting edge technology, our brilliant people have worked together throughout our history to help keep the country safe.
"This year’s GCHQ Christmas Card Challenge gives an insight into the skills we need every day as part of our mission – from languages to coding.
"But skills alone won’t be enough to crack this one. Puzzlers need to combine a mix of minds to solve the seemingly impossible."
You can download GCHQ's Christmas challenge here. Answers will be revealed on the page on 15 December.
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