The months of July and August are maddeningly busy in the South of France—it is peak summer, glorious sunshine (with just the occasional thunderstorm), and most beaches get very crowded. Offshore, Europe’s wealthy set—commodity billionaires, real estate pashas, former dictators and ageing rockstars—holidays on luxurious private yachts, discreetly. It’s another world out there where the only passport you need is access and cash, lots of it.