Boatman is back with fifty more puzzles from the Guardian and an additional five bonus puzzles previously only available online, including the notorious Referendum Day puzzle that was able to predict the result of the UK's vote over its membership of the European Union with complete confidence. Get inside the mind of one of Britain's most challenging and innovative crossword compilers, as he tells the story behind the development of each puzzle: how he thought of the theme, the ideas that didn't make it into print and the odd connections that emerged afterwards. Expect talk of crosswords and coincidences, politics and particle physics. Solve extra clues and hear from solvers who enjoyed the puzzles when they were first published. Dave Gorman writes: Put the kettle on. That's my advice. Boatman's puzzles are best served with a cup of tea. If a crossword is painting pictures with words, then every setter has his or her own style. Some create clues that remind me of a Heath Robinson cartoon - full of intricate detail and connections - while others bring to mind the simple brush strokes of an Al Hirschfeld caricature, where there can be almost nothing on the page and yet, somehow, Liza Minelli's face is staring back at you. Boatman's puzzles are Magic Eye posters. You stare at them for a while and then suddenly something three dimensional pops out as your eyes defocus. When you first scan through a puzzle, a theme may be apparent. Words will be repeated. Newspaper, newspaper, newspaper, Guardian, red-top, newspaper, newspaper, Independent. It may make you feel dizzy. So put the kettle on. Make that cup of tea. Relax. Defocus. He's a devious sod and he enjoys going back to the same source and coming back with something different. And you know that it will always be different. No two 'newspapers' are ever the same. That's his thing. Don't be dizzied by it. Dance with it. Enjoy. Then enjoy again as you get the insight from the commentaries that follow. Mine's white with no sugar. Ta.