You spot a two-letter word that starts with the free T. It has to be TO. You fill in the O, and suddenly an eight-letter word reads T _ _ O _ _ _ _ and your brain refuses to let it go. Five minutes later you’re muttering at a 135-year-old sentence about evidence. That’s the cryptogram …

You see SCARLET, MUSTARD, PLUM and BLUE, and you’re already reaching for the Submit button. Four colours, done. Except PEACOCK is sitting two tiles over, smirking. Now you have five candidates for four slots, one mistake on the board, and a creeping suspicion that this puzzle was written by …