The Bourne Ultimatum +CD: Robert Ludlum

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 that the telegrams are really a message from Bourne's mortal enemy, Carlos, also known as The Jackal, the world's deadliest and most elusive terrorist. And furthermore, they know what the Jackal wants: a final confrontation with Bourne.
Now David Webb must do what he hoped never to do again - assume the terrible identity of Jason Bourne. His plan is simple: to infiltrate the 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.
Retold by David Maule.