Complex sentence: The couple head to Paris to investigate Bourne's connection with the Treadstone Corporation: the source of the money in his account and learn that their attackers may be led by Carlos the Jackal, an assassin whose trademark is a bullet in the throat.
Split into simpler sentences: The couple head to Paris to investigate Bourne's connection with the Treadstone Corporation: the source of the money in his account. Bourne and Marie learn that their attackers may be led by Carlos the Jackal, an assassin whose trademark execution is a bullet in the throat.