A poor "lady's companion", so self-effacing that we are never given her name (Joan Fontaine), suddenly finds her life changed when a moody widower, Maxim de Winter (Laurence Olivier), proposes to marry her and take her to his splendid estate of Manderley.

It seems like a fairy-tale turned true, but it is not. On reaching Manderley, the new Mrs. de Winter (still unnamed) finds herself out of place, as Maxim seems to drift away and the hostile housekeeper Mrs. Danvers (Judith Anderson) repeatedly tells her that she will never live up to the standard set by Maxim's first wife Rebecca.

What was Rebecca really like? The perfect English lady, or a hypocrite who dazzled the people around her? Where do Maxim's affections really lie? The questions not only create a great movie mystery, but a portrait of an unequal marriage between an arrogant aristocrat and a neurotically dependent young wife.