Brontë Parrish, a horticulturalist and environmentalist, enters into a Green Card marriage with Georges Fauré, an undocumented immigrant from France, so he may stay in the United States. She uses her fake marriage credentials to rent the apartment of her dreams. After moving in, to explain his absence, she tells the doorman and neighbors he is conducting musical research in Africa.
Contacted by the Immigration and Naturalization Service for an interview to determine if the marriage is legitimate, Brontë tracks down Georges, who is working as a waiter. Although the two have little time to get their facts straight, the agents who question them appear to be satisfied with their answers. But when one of the agents asks to use the bathroom and Georges directs him to a closet, their suspicions are aroused, and they schedule a full, formal interview to be conducted two days later at their office.
Advised by her attorney that she could face criminal charges if their deception is uncovered, Brontë reluctantly invites Georges to move in with her. They try to learn about each other's past and their quirks and habits but quickly find they can barely tolerate each other. Georges is a fiery-tempered selfish slob and smoker who prefers red meat to vegetarian food, while Brontë is shown as uptight and cold, obsessed with her plants and wrapped up in environmental issues.
Meanwhile, the parents of Lauren Adler, Brontë's best friend, plan to leave New York City and consider donating their trees and plants to the Green Guerrillas, a group overseeing the development of inner-city gardens. Brontë is invited to a dinner party to discuss the issue and discovers Georges is there, having been asked by Lauren. He so impresses the Adlers with an impressionistic piano piece, set to a poem about children and trees, that they agree to donate their plants to the Green Guerrillas. When Brontë's parents later arrive at the apartment for an unannounced visit, Georges pretends to be the handyman.
When Brontë's boyfriend Phil returns from a trip, Georges reveals that he is married to her. Brontë angrily kicks Georges out, but the pair nonetheless appear at the immigration interview the next day. The two are questioned separately, and when Georges is caught out by the interviewer, he confesses the marriage is a sham. He agrees to deportation but insists Brontë not be charged for her role in the charade. He lets Brontë believe the interview was a success and the two go their separate ways.
A few days later, Georges invites Brontë to join him at the cafe where they first met. When she notices one of the immigration agents is waiting outside, she realizes Georges is being deported and tries to stop him from being sent away as they've both realized they are in love with each other.
Georges promises to write every day asking the same question
> When are you coming, chérie?
a line he had also used when describing their fabricated courtship to the INS. Just before he leaves with the immigration agent, Brontë asks if he still has their wedding rings; he pulls them out of his pocket and they quickly exchange rings again, laughing and kissing. Then Georges departs with the agent as Brontë watches from the sidewalk.