Star Wars: Dawn of the Jedi - Into the Void By Tim Lebbon

At the feet of the Masters of the ancient Je’daii Order, Lanoree Brock learned the mysteries and methods of the Force. But it’s power eluded her brother, and his bitter shunning of the Je’daii ended in tragedy. Now, after years of solitary life as a Ranger keeping order in the galaxy, Lanoree has been urgently summoned by the Je’daii Council. A fanatical cult leader, obsessed with traveling beyond known space, is bent on opening a cosmic gateway using dreaded dark matter— risking a cataclysm that will consume an entire star system. The only thing more shocking to Lanoree than the specter of galactic annihilation is being tasked by her Masters with preventing it. But a staggering revelation soon makes clear why she was chosen: the brilliant, dangerous madman she must track down and stop at any cost is the brother whose death she has long grieved— and whose life she must now fear.