Adapted from a Saturday Evening Post serial by Frank and Marian Cockrell, Dark Waters stars Merle Oberon as heiress Leslie Calvin, a woman with a neurotic aversion to water. This stems from the fact that in her childhood, Leslie was one of four survivors of a torpedoed steamship. Preying upon Leslies fears, conniving Mr. Sydney (Thomas Mitchell), a guest at the Calvin familys Louisiana plantation, concocts a campaign of terror designed to drive the poor girl crazy so that he can claim her vast inheritance. Sydney and his cohorts also have the presence of mind to murder all of Leslies closest relatives, leaving her utterly helpless. ~ Hal Erickson, All Movie Guide