Crossword blog: a really, really hard puzzle

We catch up with Enigmatist, who has been bending brains in the Listener

Around these parts, we only occasionally mention the weekend puzzles without black squares; when we do, I usually advise that curious solvers should not be terror-stricken.

I’d be lying, though, if I said that they didn’t sometimes throw up an absolute bear. With the Listener, once every decade or so, a puzzle appears that is so baffling and deceptive that solvers get in touch with each other, tersely avoiding spoilers. “4677. Got anywhere?” “Ten days in and just the perimeter.” “Stick with it, I promise.”