Moment to Moment (1966)

The French Riviera. With a lifeless body lying on her kitchen floor, Kay Stanton, the glamorous American wife of a renowned psychiatrist, is in shock. After all, the loaded pistol in the lady's hand doesn't lie--Kay has just shot a man. As Kay calls out her best friend Daphne Fields to help her, vivid flashbacks depict an ill-advised whirlwind romance filled with chance encounters, sinful desires, and remorse. Now, the French police are on the tangled case, and shrewd Inspector DeFargo already smells a rat. And the question remains. Can a moment of weakness destroy everything one holds dear?