The Vow

Two weeks before her wedding, a stranger stops Amy in the street and warns her she's in danger. Then that night, Matt, her fiance, doesn't come home. Desperate, Amy calls the police - but when Matt fails to emerge, she's forced to call off her wedding day.
Then another man is reported missing, by a woman called Fiona - a man meeting Matt's description, who was about to leave his fiancee for her. He was supposed to be moving in with her - but instead, he's vanished.
Amy refuses to believe Fiona's lover can be her Matt - but photos prove otherwise, and it soon becomes clear that Matt has been leading a double life. As the police dig deeper, two conflicting, yet equally plausible stories emerge from two women who allegedly have never met.