When actress Diana Baring is found in a daze beside her colleague’s murdered body, all evidence points to her guilt. During the trial, juror Sir John Menier doubts the verdict, but yields to pressure. Haunted by remorse, he launches his own investigation.
Francis, a young man, recalls in his memory the horrible experiences he and his fiancée Jane recently went through. Francis and his friend Alan visit The Cabinet of Dr. Caligari, an exhibit where the mysterious doctor shows the somnambulist Cesare, and awakens him for some moments from his death-like sleep.