Star Wars: The New Jedi Order: Dark Tide (abridged)

It is a perilous time for the New Republic. Just when unity is needed most, mistrust is on the rise. Even the Jedi feel the strain, as rogue elements rebel against Luke's leadership. When alien invaders known as the Yunnan Vong strike without warning, the New Republic is thrown on the defensive. Merciless warriors, the Yunnan Vong glory in torture. Their technology is as strange as it is deadly. Most ominous of all, they are impervious to the Force.

The alien Yuuzhan Vong have launched an attack on the worlds of the Outer Rim. They are merciless and they stand utterly outside the Force. Even the Jedi are rendered helpless by this impervious foe, and their solidarity has begun to unravel. While Luke struggles to keep the Jedi together, Knights Jacen Solo and Corran Horn set off on a reconnaissance mission to the planet Garqi. There they uncover a secret that might be used to undermine the enemy - if only they can stay alive long enough to use it!