Having lived well beyond his means, César Borgnoli, an Italian car dealer, is on the brink of ruin. His sister Alex, who lives with her girlfriend Kim, offers to save the family business by cutting him a deal. César must pretend to be Kim's husband so that they can go to Thailand to legally adopt little Maily, an adorable 5-year-old girl that Alex and Kim long to welcome in their home.
César imagines that it'll just be a matter of a weekend trip during which he can combine business and pleasure. However, the vibe is bad between him and Kim, his "new wife." And then there's the local police, Chinese triads, and a few heads of stuffed fish... The weekend quickly becomes a nightmare. The phoney couple has barely arrived at the airport when they're greeted by Doctor Luix, the orphanage's doctor, a neurotic, grumpy widower who believes in traditional weddings and is very attached to Maily.
The scrupulous doctor accompanies César and Kim on their adventure to reassure himself that they are the perfect parents for the little girl, and above all to verify that they form a real couple.
Faced by the spectacle of this pair who never stop bickering, Doctor Luix is initially surprised, then becomes amazed. Then comes the day that he is stopped in his tracks by gorgeous Alex, who arrives in Bangkok to get her brother out of jail.