How The Thirty-Nine Steps invented the modern thriller

The novel – “one of the finest thrillers ever written,” declared the Telegraph – was serialised in Blackwood’s Magazine during the summer of 1915 and published as a book that October. Broadstairs inspired its seaside climax – and its curious title. “His daughter, my late aunt Alice, used to count the steps as they went down to the beach from the cliff,” James Buchan, John’s grandson and a novelist himself, tells me, adding that during the Forties those old oak steps were ripped out of the cliffs. The 39th was saved by a builder and sent to the family.