Meak head clerk Kees Popinga realises at the same time as the police that owner De Koster has stripped his Dutch company clean because of his infatuation with Parisian girl Michelle. After a confrontation between the two men De Koster ends up dead and Popinga makes off to Paris with the remaining money. There he contacts Michelle, with the police in close pursuit.

In Groningen, Holland, bookkeeper Kees Popinga stops to watch a train pass as he bicycles to work. At his office he is visited by his unemployed friend Merkemans. When Popinga's boss, Julius de Koster, Jr., and his elderly father stop by, Popinga inquires about a position for Merkemans. However, de Koster refuses to hire Merkemans because he had been managing director of a company that closed due to corruption. Later that day, Paris police inspector Lucas introduces himself to de Koster and, after asking to see de Koster's books, explains that he is investigating a recent influx of Dutch money in the Paris black market. Both de Koster and Popinga assure Lucas of their integrity and invite him to inspect their bookkeeping. That night, as Popinga tells his wife Maria about his day, he hears the evening train whistle, which prompts him to dream of traveling to Paris. He then departs for the chess club, where de Koster has invited Lucas to play. Along the way, Popinga observes de Koster kissing an unfamiliar woman at the train station. Later at the club, Lucas shows de Koster a picture of the woman and asks if he knows her. De Koster claims he does not, and Popinga plays along with his boss. That night, Popinga, who has invested all his savings in de Koster's company, fears that his business will go the way of Merkemans' company. Although it is after business hours, Popinga goes to the office and discovers that de Koster is burning the accounting books. De Koster admits that he fell in love Michèle, the woman in the photograph, on a business trip to Paris and that, having embezzled money for her, the company is now ruined. Popinga follows de Koster to the canals where his boss shows him a note that reads "Death before dishonor." Fearing de Koster will commit suicide, Popinga attempts to intervene and accidentally knocks the briefcase out of his hand, which then springs open to reveal a train ticket to Paris and bundles of cash. Infuriated, Popinga attacks de Koster, who falls backwards into the canal, hits his head on a boat and sinks underwater. Popinga cries for help, then scoops up the briefcase and runs for the train to Paris. To his surprise, Lucas joins him in his compartment and probes him for information about his destination and his employer. Popinga claims that de Koster has sent him to Paris to borrow money to save the company. After a stop in Quevy, Lucas, who hopes to trick Popinga into revealing the truth, tells him that de Koster has been shot to death. Popinga insists that de Koster committed suicide and the next morning, jumps off the train before it reaches the station, and seeks out Michèle, whose address is inside the briefcase. After pushing her lover and black market cohort Louis out the back door, Michèle is surprised to greet Popinga rather than de Koster, whom she expected to arrive with the money. Popinga tells her about de Koster's death and warns her that Lucas is investigating her, but when he suggests a romantic liaison, Michèle mocks him and throws him out. Popinga then wanders along the Champs Elysees until he bumps into a woman who helps him find a room to rent. Lucas, meanwhile, questions Michèle and asks for her help in finding Popinga, who he fears will soon be corrupted as he believes he murdered de Koster. After Lucas reveals that Popinga has de Koster's money, Michèle tracks down the bookkeeper and takes him to Louis' apartment overlooking a garage and the train tracks, claiming that Louis will obtain false identification papers for him. A distrustful Popinga secretly stashes the money in an abandoned car outside, and his suspicions are confirmed when Louis searches his room. Although Louis is impatient for the money, Michèle insists on obtaining it in her own manner. Later that night, Michèle admits to Popinga that she is interested only in his money, and then further injures his pride by insulting his capacity for love. Her provocation is successful when the next night, Popinga seeks her out at a nightclub, where she is attempting to seduce an older American businessman. Popinga, desperate for adventure, vows to risk his money if she will join him for an evening of entertainment. Michèle consents and later, drunk on champagne, Popinga telephones Lucas to taunt him. Lucas attempts to warn Popinga that he may be passing bad money, but Michèle hangs up the phone. After a besotted Popinga admits to hiding the money in a car, he falls asleep in Michèle's apartment, and she slips out to find the cash. Lucas, however, has already located it and takes her into custody, insisting that she bring him to Popinga. Popinga awakens as they arrive and overhears Lucas telling Michèle he will drop all charges against her as long as he can apprehend Popinga. Popinga escapes, unaware that Lucas is merely trying to prevent him from further harm. Haunted by visions of a mocking Michèle, Popinga breaks a shop window and steals a knife, then forces Louis to call Michèle and insist that she come over. Popinga then slashes Louis and later murders Michèle. Deranged, Popinga runs onto the tracks in front of an oncoming train, but falls to the side before being struck. When Lucas finds him, Popinga is delusional, and asks Lucas' assurance that nothing was ever wrong with his bookkeeping.