The Bourne Legacy, which is written by Eric Lustbader instead of Ludlum.
I wondered where the series might go. In this one we find Bourne lured to Conklin's house, where he finds Alex and Mo dead, killed by someone. As he's processing this, police are arriving, and he must disappear. He knows he's been set up and is on the run. As he's trying to escape, Khan, an international assassin attacks him, but they manage to turn the tables on each other and separate.
The writing is definitely more modern here, and different. Bourne is more logical, and the flow is smoother, less distracted. The last book by Ludlum was choppy, almost frantic and panic'd in the writing at times. This one is easier to follow and move on.
We find Bourne on the run, a worldwide sanction against him, and he must evade the CIA as he makes his way to Paris and then Budapest. Meanwhile there is a Hungarian humanitarian that is backing a Chechan terrorist group for some reason, planning on releasing a biological weapon at a peace summit in Iceland. As the tales wind in the book, we have the terrorists, Bourne, and Khan chasing one another and doing battle.
Khan's relationship with Bourne is complex and it's one that develops in each of their minds throughout the book. It's an interesting read, and I enjoyed it, but was a little thrown by the fact that Bourne doesn't seem to feel his age in this one, when he did in the last one. A little inconsistency, but it makes me wonder what will happen in the next book.