Summary (The movie is a good rendition of the book):

Michael Lander (played by Dern in the film) an American blimp pilot, made psychotic by his treatment as a prisoner of war during the Vietnam War, and frustrated by the lack of sympathy shown to him by the government that sent him there, decides to hook up with a palestinian terrorist group known as Black September, in order to detonate a shrapnel bomb housed in a blimp undercarriage, over a football stadium during the Superbowl, causing thousands of deaths. The only man who can stop him is David Kabakov (played by Shaw), an Israeli-government assassin who will stop at nothing to prevent the catastophe.