“When I started writing books for children, I knew what interested me,” Daniel Handler writes early on in his new memoir And Then? And Then? What Else?. “Terrible things happening, like in all the best literature.” Now there’s a man who understands his own muse. Writing as Lemony Snicket, in A Series of Unfortunate Events, Handler has been true to that muse. He piled terrible thing on terrible thing with an insouciant sweetness and lugubrious humour little rivalled in con...