Viktor Navorski is a man without a country; his plane took off just as a coup d'etat exploded in his homeland, leaving it in shambles, and now he's stranded at Kennedy Airport, where he's holding a passport that nobody recognizes. While quarantined in the transit lounge until authorities can figure out what to do with him, Viktor simply goes on living – and courts romance with a beautiful flight attendant.

An alien is left behind on Earth and saved by the 10-year-old Elliot who decides to keep him hidden in his home. While a task force hunts for the extra-terrestrial, Elliot, his brother, and his little sister Gertie form an emotional bond with their new friend, and try to help him find his way home.