There are some spoilers ahead, so I must warn you that if you not seen or heard about this movie, then stop reading further and run down to your nearest DVD library or wherever you can locate this gem of a movie.
Spoorloos a.k.a. The Vanishing, directed by George Sluizer is a Dutch/French thriller based on the novel "The Golden Egg" by Tim Krabbe who has also written the screenplay for the movie. It begins with a young Dutch couple Rex and Saskia on their way to Tour De France. They halt near a gas station on the way and Saskia gets down to buy some refreshments. When Saskia doesn't return, Rex starts searching for her in vain for the next three years. The story then shifts to Raymond's perspective, who is a regular French guy with a wife and two kids and the one who has kidnapped Saskia. We are shown how Raymond prepares for the kidnap with some humorous unsuccessful attempts. After three years of Saskia's disappearance, Rex suddenly starts getting postcards from the kidnapper and he decides to launch a fresh search campaign. Raymond one day reveals himself to Rex and offers him to tell everything about Saskia provided he accompanies him to France. Rex's curiosity to know the whereabouts of Saskia makes him accept the deal and they both start for France. On the way to France, Raymond reveals more about his character and the motivation behind the kidnap.