GCHQ has sent out a Christmas card - how nice! Except this card comes with an infuriating challenge - can the "wise men and women in your household" solve its annual festive puzzle?
Rather than a picture of a snowman or jolly Santa, the intelligence service has hidden its festive greeting in cryptic code.
Jeremy Fleming, the director of GCHQ, sent the card to "colleagues and partners across the world" before it was made public.
Are you up for cracking the code? This year, the card features a festive bauble which contains a circuit board pattern with room for nine answers.
Read more on mirror.co.uk