The water taxi idled up to the fabled Hotel Excelsior on the Lido in Venice for my rendezvous with Contessa Marina Cicogna. As good a first line to a roman à clef as any. Inside, an unsympathetic renovation was thrown into stark relief by photographs evoking the romance and swagger of the hotel’s storied past, when Pierpont Morgan declared that “those who have visited Europe talk more of the Excelsior Palace than they do of the Doge’s.”

We were due to meet in the Blue Bar, which on a hot and sunny day in July was deserted. Outside, the Adriatic glittered. A bartender who looked barely old enough to drink was my only companion.