The idea for the film came when Emmerich and Devlin were in Europe promoting their film "Stargate". A reporter asked Emmerich why he made a film with content like "Stargate" if he did not believe in aliens. Emmerich stated he was still fascinated by the idea of an alien arrival, and further explained his response by asking the reporter to imagine what it would be like to wake up one morning and to discover 15 mile-wide spaceships were hovering over the world's largest cities. Emmerich then turned to Devlin and said, "I think I have an idea for our next film."