Logan Gonzago Mountstuart, writer, was born in 1906, and died of a heart attack on October 5, 1991, aged 85. William Boyd's novel Any Human Heart is his disjointed autobiography, a massive tome chronicling "my personal rollercoaster"--or rather, "not so much a rollercoaster", but a yo-yo, "a jerking spinning toy in the hands of a maladroit child." From his early childhood in Montevideo, son of an English corned beef executive and his Uraguayan secretary, through his years at a Norfolk public school and Oxford, Mountstuart traces his haphazard development as a writer. Early and easy success is succeeded by a long half-century of mediocrity, disappointments and setbacks, both personal and professional, leading him to multiple failed marriages, internment, alcoholism, and abject poverty.

Mountstuart's sorry tale is also the story of a British way of life in inexorable decline, as his journey takes in the Bloomsbury set, the General Strike, the Spanish Civil War, 1930s Americans in Paris, wartime espionage, New York avant garde art, even the Baader-Meinhof gang--all with a stellar supporting cast. The most sustained and best moment comes mid-book, as Mountstuart gets caught up in one of Britain's murkier wartime secrets, in the company of the here truly despicable Duke and Duchess of Windsor. Elsewhere Boyd occasionally misplaces his tongue too obviously in his cheek--the Wall Street Crash is trailed with truly crashing inelegance--but overall Any Human Heart is a witty, inventive and ultimately moving novel. Boyd succeeds in conjuring not only a compelling 20th century but also, in the hapless Logan Mountstuart, an anti-hero who achieves something approaching passive greatness.