On May 6, 2014, the sun was still high over Nice, France, when Hélène Pastor, 77, left L’Archet public hospital and was ambushed and murdered in a barrage of gunfire.
She was known as Monaco’s richest woman, reportedly worth as much as $25 billion. But even before her murder, 2014 had been an annus horribilis for her. On January 26, her dashing son, Gildo, 47—co-founder, along with Leonardo DiCaprio, of a Formula E– style electric-car racing team, and owner of an electric-car consumer brand called Venturi— suffered a devastating stroke, which left him partially paralyzed and unable to speak. A little more than a week later, Hélène buried her brother, Michel, known as “the Boss of Monaco.” His death, at 70, after a long illness, left her as the last…