I love seaside books. Books about long empty beaches, old towns stuck in time and mysterious things that wash up on beaches. Or pop out of clam shells, like the toy twins discovered by young Mary in William Nicholson’s practically perfect The Pirate Twins.

Published in 1929, around the time of Hergè’s Tintin in the Congo and Jean de Brunhoff’s Babar the Elephant, The Pirate Twins is a product of the same Colonialist world as those difficult books. Instead of giving us savages to be conquered, William Nicholson celebrates freedom and offers a touching interracial friendship.

The Pirate Twins aren’t the leering golliwogs of Enid Blyton, they are feral, joyous creatures who love to dance, sing and put things in the cat’s milk. They are children.

Maurice Sendak considered it, ‘The first – the best – the most gloriously original modern picture book of all time.’ It’s a story he cited as being a major inspiration forWhere the Wild Things Are. Think of the twins as a combination of both Max and the Wild Things you’re be getting close.

Nicholson’s innovative and sparing use of words also links Where the Wild Things Are, with sentences that end on a beat and lead you breathlessly into the next plate. There are just over 100 words in this adventure, but the pictures invite us to think far beyond the beachside, to Jamaica, through towering seas and into the Milky Way.At the same time there remains the beach, a domestic paradise that is home to Mary, who indulges her young visitors with lobster, wine, dancing and dominoes. But the twins are pirates and become restless ‘until one fine day they left a note and stole a boat and sailed away to sea.’

Of course the errant boys return, bold as brass to eat Mary’s birthday cake. And they’ve been returning ever since. Any children’s story that unleashes a wild or uncontrollable child or creature on a ‘civilised’ family life is following in the footsteps of the Pirate Twins.