He manages to escape the interrogation room and has various adventures on the lam until Olham and his wife (Madeleine Stowe) are trapped by government troops in a forest near an alien crash site. When one half of the cockpit is pulled away, revealing the murdered corpse of Olham's real wife, the government troops turn their guns on the surprised clone to prevent her bomb from detonating. However, when the other half of the cockpit is pulled back, revealing Olham's corpse, the other Olham finally realizes he was indeed the clone the government thought he was. The words he utters on seeing the real Oldham's corpse causes the detonation sequence to engage. Hathaway turns around at the last moment to see Oldham's eyes turn black and the bomb in his chest explode, destroying everything within several miles and claiming the lives of thousands of people.
The film adaptation was originally planned to be one segment of a three-part sci-fi anthology film before it was decided to expand it to feature length. Originally shot in 2000, the oft-delayed film was finally released in 2002 and received a lukewarm reception.
The film also used selected scenes and props from the movie Starship Troopers. For example, the scene of medics clearing rubble after the bomb is taken directly from the news reel shown after the "bug meteor" attack in Starship Troopers. The soldiers in Impostor also use the same armor as the troopers in Starship Troopers. A handful of other clips of rockets and meteor attacks were taken from the films Gattaca and Armageddon.
The movie made $6,114,237 on an estimated $40 million budget.
Critical reaction to Impostor was mixed. James Berardinelli of ReelViews gave the film two and a half stars (out of four), saying "there are a few moderately diverting subplots and the storyline eventually gets somewhere," but added that "Impostor wears out its welcome by the half-hour mark, and doesn't do anything to stir things up until the climax. You could spend the entire midsection of this movie in the bathroom and not miss much.
William Arnold of the Seattle Post-Intelligencer gave the film a mildly positive review, praising lead actor Gary Sinise's ability to "hold the film together and provide a strong, sympathetic human focus. Maitland McDonagh of TV Guide gave the film three stars out of four, saying it packed "a real emotional wallop," but suggested that it would have worked better as the 40-minute short film it was originally intended to be.
Keith Phipps of The Onion's A.V. Club gave the film a negative review, saying that "it essentially uses the setup of [the story] as a bookend to one long, dull chase scene. Robert Koehler of Variety also criticized the film, calling it "a stubbornly unexciting ride into the near future.