BBY/ABY is used to position items along the Star Wars Timeline. BBY refers to Before the Battle of Yavin. ABY refers to After the Battle of Yavin. The Battle of Yavin in Episode IV: A New Hope occured in 0 BBY/ABY.
On a quest to learn the secret behind his nephew’s fall to the dark side and restore the Jedi Order to its rightful place in the galaxy, Luke Skywalker and his son Ben find themselves surrounded by Sith. Yet it turns out the Sith aren’t the biggest threat, and their High Lord makes Skywalker a previously unthinkable offer. With unexpected allies, father and son head off to face the source of the psychosis plaguing the Jedi Knights.
What began as a quest for truth has become a struggle for survival for Luke Skywalker and his son, Ben. They have used the secrets of the Mind Walkers to speak with the spirits of the fallen, risking their lives in the process. They have faced a team of Sith assassins and beaten the odds to destroy them. And now the death squad’s sole survivor, Sith apprentice Vestara Khai, has summoned an entire fleet of Sith frigates to engage the embattled father and son. But the dark warriors come bearing a surprising proposition that will bring Jedi and Sith together in an unprecedented alliance against an adversary more ancient and alien than they can imagine. For in the treacherous web of black holes that is the Maw, the Skywalkers and their Sith allies will have to fight an unimaginable evil, and Luke will be rocked by a staggering truth.