When I was a child, my favourite Roald Dahl story was Skin, a macabre tale about an old tattooist named Drioli, who has a magnificent work of art tattooed on his back by the famous painter Chaïm Soutine. One day he happens upon an exhibition of the dead artist’s work in a fancy Paris gallery, and recalling the tattoo on his back, he decides to go inside and take a closer look. Having fallen on hard times and now reduced to begging for a living, he is not welcome amongst the wealthy art patrons – until he reveals the original artwork permanently inked into his skin. The gallery owner immediately offers him a large sum of money for the tattoo: “But how,” Drioli asks, “can I possibly sell it?”

The gallery owner suggests that he have the tattoo removed by skin graft operation, and offers to pay a handsome…