Just as the mystery of Jack the Ripper continues to grip the English imagination, the case of the Papin sisters of Le Mans — two maids who, in 1933, brutally slaughtered their employer and her daughter — holds a peculiar sway over the French. Jean Genet used the ghastly events as the basis for his celebrated one-act play "The Maids," while the cream of France's intelligentsia, from Jean-Paul Sartre and Simone de Beauvoir to Jacques Lacan, have searched for answers to the questions raised by the Papins' bizarre crime. Jean-Pierre Denis's scorching film — one of the most harrowing true-crime dram...