In the summer of 1885, three Frenchmen arrived in London for a few days’ shopping. One was a Prince, one was a Count, and the third was a commoner with an Italian name, who four years earlier had been the subject of one of John Singer Sargent’s greatest portraits.

The three men's lives play out against the backdrop of the Belle Epoque in Paris. The beautiful age of glamour and pleasure more often showed its ugly side: hysterical, narcissistic, decadent and violent, a time of rampant prejudice and blood-and-soil nativism, with more parallels to our own age than we might imagine.

Our guide through this world is the Samuel Pozzi, society doctor, pioneer gynaecologist and free-thinker, a rational and scientific man with a famously complicated private life.

The Man in the Red Coat is at once a fresh and original portrait of the French Belle Epoque – its heroes and villains, its writers, artists and thinkers – and a biography of a man ahead of his time. Witty, surprising and deeply researched, the new book from Julian Barnes illuminates the fruitful and longstanding exchange of ideas between England and France, and makes a compelling case for keeping that exchange alive.