The Bourne Ultimatum

The world's two deadliest spies in the ultimate showdown. At a small-town carnival two men, each mysteriously summoned by telegram, witness a bizarre killing. The telegrams are signed Jason Bourne. Only they know Bourne's true identity and understand the telegram is really a message from Bourne's mortal enemy, Carlos, known also as the Jackal, the world's deadliest and most elusive terrorist. And furthermore, they know that the Jackal wants: a final confrontation with Bourne. Now David Webb, professor of Oriental studies, husband, and father, must do what he hoped he would never have to do again—assume the terrible identity of Jason Bourne. His plan is simple: to infiltrate the politically and economically Medusan group and use himself as bait to lure the cunning Jackal into a deadly trap—a trap from which only one of them will escape.
From the Paperback edition.