The Locket (1946)

Lovely Nancy seems like the ideal bride to fiancé John Willis... until, just before the ceremony, he is approached by Harry Blair, who claims to be Nancy's ex-husband. The tale Blair unfolds, in a flashback within a flashback within a flashback, paints Nancy as a kleptomaniac, habitual liar--and perhaps worse. But is Blair telling the truth? And does fate have another surprise in store?