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These puzzles have been set by the experts at GCHQ. The difficulty levels are gauged using the Enigma Rotor Scale, which you can find described at https://www.gchq.gov.uk/information/enigma-rotor-scale

  1. Very easy. Should be quickly solvable. 
  2. Not too hard but not immediately obvious. You probably need to make a cup of tea for this one. Coffee works too. 
  3. Getting a bit hard now. Tea drinking will help, but a bit of pacing around the room is probably in order as well. 
  4. Something of a meaty challenge and probably one you might need to collaborate with other people to solve. 
  5. Very difficult and time consuming. There might well be multiple answers. But, then again, maybe there’s just one answer. 
  6. At this level it might be far from obvious even what the question is asking, never mind how you might go about solving it.  Good luck!

  • GCHQ Puzzle Solution 11

    Chain of verbal reasoning

    1. This country (LAOS) is an anagram (ALSO) of a synonym (TOO) of a homophone of a prime number TWO) and a homophone (LOUSE) of an anagram of a capital city (SEOUL).
    2. This ex Prime Minister’s surname (CAMERON) is an anagram (ROMANCE) of a synonym (LOVE) of an anagram of a rodent (VOLE).
    3. This emotion (FEAR) is an anagram (FARE) of a homophone (FAIR) of an antonym (FOUL) of a homophone (FOWL) of an anagram of a canine animal (WOLF) that is a synonym (EAT) of an anagram (ATE) of a homophone of a single digit number (EIGHT).

    No hints from Harry this week, so well done to those of you who completed the chain of verbal reasoning on at least one of the questions.

    We had a rather interesting proposal for an alternative solution to Question 2 from Madness:

    This ex Prime Minister’s surname (EDEN) is an anagram (NEED) of a synonym (LOVE) of an anagram of a rodent (VOLE).

    Bonus marks for inventiveness and for passion!

  • GCHQ Puzzle Challenge 11

    Chain of verbal reasoning

    1. Which country is an anagram of a synonym of a homophone of a prime number and a homophone of an anagram of a capital city?
    2. Which ex Prime Minister’s surname. is an anagram of a synonym of an anagram of a rodent?
    3. Which emotion is an anagram of a homophone of an antonym of a homophone of an anagram of a canine animal that is a synonym of an anagram of a homophone of a single digit number?

    The questions say it all this week. Can you complete the chain of verbal reasoning? As usual, post solutions to the Forum, giving the full chain in each case to show your reasoning!

  • GCHQ Puzzle Solution 10

    Strange symmetry

    For the late May Bank Holiday we brought you an extraordinarily Cryptic Crossword from the devious minds at GCHQ. The beautifully formatted solution was provided for us by competitor Gordonwelshman. Thank you!

    Hope you enjoyed it!

    1 A black viscous substance TAR
    2 Academic DON
    3 Affectionate name for Father POP
    4 Affectionate name for Mother MA
    5 Affectionate name for female sibling SIS
    6 Akela was one WOLF
    7 Album by U2 WAR
    8 Aquatic creature EEL
    9 Artic Monkeys album AM
    10 Armed Conflict WAR
    11 Australian spin bowler AGAR
    12 Belief held as absolute fact TENET
    13 Belonging to a character from The Sword in the Stone WARTS
    14 Betray RAT
    15 British army special unit SAS
    16 Charature fromThe Tribe GEL
    17 Computer programming language ADA
    18 Daughter of Mara RAGA
    19 Degree MA
    20 Eat very quickly WOLF
    21 Egyption sea port SUEZ
    22 Enthusiastic AVID
    23 Famous Trojan horse malware ZEUS
    24 Finnish thrash metal album RAJA
    25 Fizzy drink POP
    26 Former CIA Director TENET
    27 Former Home Secretary STRAW
    28 Friends PALS
    29 Greek god EROS
    30 Greek island RO
    31 Growths WARTS
    32 Heraldic colour OR
    33 Improvised Indian music RAGA
    34 Incline the head NOD
    35 Indian monarch RAJA
    36 King of the gods ZEUS
    37 Limb LEG
    38 MI6 SIS
    39 Male or female name LEE
    40 Mauritian town AJAR
    41 Methode of detecting distant objects RADAR
    42 Metonym for 1956 war SUEZ
    43 Morning AM
    44 Movement of fluid FLOW
    45 Nickname of 2000 Olympics swimmer EEL
    46 Nickname of M*A*S*H character RADAR
    47 Open-handed blow SLAP
    48 Painful SORE
    49 Part of a journey LEG
    50 Popular name of famous London statue EROS
    51 Rodent RAT
    52 Sailor TAR
    53 Scandinavian airline SAS
    54 Self-important person DIVA
    55 Semi-solid colloid GEL
    56 Slang for being annoyed SORE
    57 Slang for make-up SLAP
    58 Slightly open AJAR
    59 The rising movement of the tide FLOW
    60 The side away from the wind direction LEE
    61 Town in Egypt AGA
    62 Type of audio format RAW
    63 Type of cooker AGA
    64 Type of Fijian chief RO
    65 Type of gate OR
    66 Type of WWI battalion PALS
    67 Type of jelly AGAR
    68 Uncooked RAW
    69 Woman’s name ADA
    70 Yellowish beige STRAW

  • GCHQ Puzzle Solution 9

    Long division

    The solution this week comes from the first person to crack it, Kford-Academy. Well done!

    Divide the following names into two groups:

    Ada, Diana, Egon, Flo, Ida, Kent, Nev, Wes

    The one that can go into both groups is Ida. Here are the groups.

    Group 1 (starting US states):
    Flo (Florida)
    Ida (Idaho)
    Kent (Kentucky)
    Nev (Nevada)
    Wes (West Virginia)

    Group 2 (ending US states):
    Ada (Nevada)
    Diana (Indiana)
    Egon (Oregon)
    Ida (Florida)

  • GCHQ Puzzle Challenge 9 – Harry’s Hint

    Long division

    The clue here is provided by competitor Puttput86:

    “Al, Georg and Mary could also go in one of the groups!”

    Divide the following names into two groups:

    Ada, Diana, Egon, Flo, Ida, Kent, Nev, Wes

    Which one can go in either group?

  • GCHQ Puzzle Challenge 10

    Strange symmetry

    For the late May Bank Holiday we bring you an extraordinarily Cryptic Crossword from the devious minds at GCHQ.

    The grid is symmetrical, and so are the solutions! You have no numbers to guide you in placing them, but the symmetry and the clues should together be enough.

    In an act of generosity we have filled in four of the answers for you to give you the idea! (Now the right way round.)

    Hope you enjoy it!

    (If you want us to check your answers, you can just post the words you use in the same order as the clues appear here.)

  • GCHQ Puzzle Challenge 9

    Long division

    Not sure how long this one will take you, hence the name, but we will put up a bonus challenge for the Bank Holiday Monday in case you get it quickly!

    Divide the following names into two groups:

    Ada, Diana, Egon, Flo, Ida, Kent, Nev, Wes

    Which one can go in either group?

  • GCHQ Puzzle Solution 8

    Box Office Smashes

    Fans of Richard Osman’s House of Games might recognise this. Have fun. And if Richard is taking part, please do let us know!) As usual, post your solutions on the Forum, with your time, and if we can get round to it we will edit them out and leave you the glory.

    1. Esther Blodgett is injured in combat and becomes an anti-war activist.

      A Star is Born on the Fourth of July
    2. A medic, sacked after being caught on the roof of the nurses’ home, visits Nepal to acquire new skills.

      Carry On Doctor Strange
    3. A Cheltenham man foils a Nazi plot.

      Eddie the Eagle Has Landed
    4. A spy on the hunt for a Soviet encryption device gets involved in the romantic entanglements of eight different couples.

      From Russia With Love Actually
    5. A bookstore worker has a facial transplant and becomes a fashion model.

      Funny Face/Off
    6. A jaded weatherman repeatedly hides from zombies in an underground military bunker.

      Groundhog Day of the Dead
    7. After Cliff Richard runs over a pedestrian with his bus, he is stalked by a mysterious hook-wielding figure.

      I Know What You Did Last Summer Holiday
    8. In a dystopian future, an American book collector swaps letters with a London bookseller.

      Nineteen Eighty-Four Charing Cross Road
    9. A repressed butler is separated from his son during a climate change disaster.

      Remains of the Day After Tomorrow
    10. At the age of 121, a mouse recounts the story of his life to a historian.

      Stuart Little Big Man
    11. An actress is sacked from her role on a soap opera, and can only get VoiceOver work on a Tarzan spoof.

      The Killing of Sister George of the Jungle
    12. Mr Dashwood discusses his family’s prospects with Cole Sear.

      The Sixth Sense and Sensibility
    13. A man hires a private investigator to track down his former prom date, who is now working as a nanny.

      There’s Something About Mary Poppins
    14. A football manager takes charge of the Midwich team, but his tenure only lasts for a month and a half.

      Village of the Damned United

  • GCHQ Puzzle Challenge 8 – Harry’s hint

    Box Office Smashes

    Fans of Richard Osman’s House of Games might recognise this. Have fun. And if Richard is taking part, please do let us know!) As usual, post your solutions on the Forum, with your time, and if we can get round to it we will edit them out and leave you the glory.

    1. Esther Blodgett is injured in combat and becomes an anti-war activist.

      A Star is Born + Born on the Fourth of July =
      A Star is Born on the Fourth of July

      Get the idea?
    2. A medic, sacked after being caught on the roof of the nurses’ home, visits Nepal to acquire new skills.
    3. A Cheltenham man foils a Nazi plot.
    4. A spy on the hunt for a Soviet encryption device gets involved in the romantic entanglements of eight different couples.
    5. A bookstore worker has a facial transplant and becomes a fashion model.
    6. A jaded weatherman repeatedly hides from zombies in an underground military bunker.
    7. After Cliff Richard runs over a pedestrian with his bus, he is stalked by a mysterious hook-wielding figure.
    8. In a dystopian future, an American book collector swaps letters with a London bookseller.
    9. A repressed butler is separated from his son during a climate change disaster.
    10. At the age of 121, a mouse recounts the story of his life to a historian.
    11. An actress is sacked from her role on a soap opera, and can only get VoiceOver work on a Tarzan spoof.
    12. Mr Dashwood discusses his family’s prospects with Cole Sear.
    13. A man hires a private investigator to track down his former prom date, who is now working as a nanny.
    14. A football manager takes charge of the Midwich team, but his tenure only lasts for a month and a half.

  • GCHQ Puzzle Challenge 8

    Box Office Smashes

    Fans of Richard Osman’s House of Games might recognise this. Have fun. And if Richard is taking part, please do let us know!) As usual, post your solutions on the Forum, with your time, and if we can get round to it we will edit them out and leave you the glory.

    1. Esther Blodgett is injured in combat and becomes an anti-war activist.
    2. A medic, sacked after being caught on the roof of the nurses’ home, visits Nepal to acquire new skills.
    3. A Cheltenham man foils a Nazi plot.
    4. A spy on the hunt for a Soviet encryption device gets involved in the romantic entanglements of eight different couples.
    5. A bookstore worker has a facial transplant and becomes a fashion model.
    6. A jaded weatherman repeatedly hides from zombies in an underground military bunker.
    7. After Cliff Richard runs over a pedestrian with his bus, he is stalked by a mysterious hook-wielding figure.
    8. In a dystopian future, an American book collector swaps letters with a London bookseller.
    9. A repressed butler is separated from his son during a climate change disaster.
    10. At the age of 121, a mouse recounts the story of his life to a historian.
    11. An actress is sacked from her role on a soap opera, and can only get VoiceOver work on a Tarzan spoof.
    12. Mr Dashwood discusses his family’s prospects with Cole Sear.
    13. A man hires a private investigator to track down his former prom date, who is now working as a nanny.
    14. A football manager takes charge of the Midwich team, but his tenure only lasts for a month and a half.

  • GCHQ Puzzle Solution 7

    Architecture Dreaming

    Something of an amuse-bouche to entertain you while you continue to struggle with GCHQ Puzzle Challenge 6!

    You would think the Pentagon would be the most obvious answer, though in fact more people chose the Baltimore World Trade Centre as their pick of the world’s five sided buildings. The arithmetic is on the number of sides of each of the named ones. Well done if you got it!

  • GCHQ Puzzle Solution 6

    VE Bank Holiday Crossword

    Something completely different for the Bank Holiday Weekend! At first sight you might think we have made an error with the letter counts, but the GCHQ geniuses mean exactly what they say!

    This is a crossword with a twist – each cell contains exactly one letter, but 38 characters are used in all! They all come from the English and Greek alphabets, and we have filled in a couple of the answers to help you get started:

    1 Across: Pupil (P U Pi L)

    1 Down: Prize task (geddit? Zeta in the middle!)

    We will be back on Sunday with another challenge! (and a hint for this one, but not the solution – you will have all weekend to try it!)

  • GCHQ Puzzle Challenge 6 – Harry’s Last Hint

    VE Bank Holiday Crossword (Now with a couple of the answers supplied to get you started)

    Something completely different for the Bank Holiday Weekend! At first sight you might think we have made an error with the letter counts, but the GCHQ geniuses mean exactly what they say!

    This is a crossword with a twist – each cell contains exactly one letter, but 38 characters are used in all! They all come from the English and Greek alphabets, and we have filled in a couple of the answers to help you get started:

    1 Across: Pupil (P U Pi L)

    1 Down: Prize task (geddit? Zeta in the middle!)

    We will be back on Sunday with another challenge! (and a hint for this one, but not the solution – you will have all weekend to try it!)

  • GCHQ Puzzle Challenge 7 – Harry’s Hint

    Architecture Dreaming – you might need to come up with a plan to solve this one.

    Something of an amuse-bouche to entertain you while you continue to struggle with GCHQ Puzzle Challenge 6!

  • GCHQ Puzzle Challenge 7

    Architecture Dreaming

    Something of an amuse-bouche to entertain you while you continue to struggle with GCHQ Puzzle Challenge 6!