Off Topic: On the subtle mystery of Sam & Dave Dig a Hole

I feel instinctively that a good children's book should be two things at once. Take something like Home, by Carson Ellis. On one level this is an imaginative exploration of the various ways that various people might live. People who might find a home in a shoe, say, or perched at the top of a mountain. But a good children's book should be two things at once, and the deeper, most satisfying aspect of Home involves tracking a number of items that pop up across the sweep of the book's individual pages - a tea cup, a flag - and then seeing them arranged in the final home we get to see, which happens to be Carson Ellis' home where she creates her art.

Sam & Dave Dig a Hole is two things in one. And that's hardly surprising, really, as it's the result of one of the most ideal partnerships in all of children's books - words by Mac Barnett, and pictures by Jon Klassen.

Real talk: I would like to be friends with both these people. Barnett is a writer of astonishing range and precision, a playful scamp in one book, while reaching more soulful depths in the next. He's a dandy, but a dandy who can play any tune, match any beat. Klassen, meanwhile - and apologies to Oli Welsh, who made this connection first - is Samuel Beckett. The writer, not the time traveler - but who knows? He's Samuel Beckett with a few more jokes. And much else besides. His watercolours - I think they're watercolours - have a glorious way of bringing out the thickness and density of the paper they're spread across: they capture that feeling when good paper gets damp and takes on a felty quality. Klassen is also very skilled when it comes to capturing starkness and surprise in the faces of his characters. He is the ideal illustrator for stories which involve the blunt limitations of language - the places where it stops short and fails everyone.

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