Troubled by Asajj Ventress' growing prowess with the dark side of the Force, Darth Sidious commands Count Dooku to eliminate her. But Ventress survives Dooku's assassination attempt, and the jilted former apprentice vows to take revenge, enlisting the aid of her kinswomen -- the mystical Nightsisters -- in her sinister scheme. Mother Talzin, leader of the Nightsisters, veils Asajj and her fellow assassins in a cloak of invisibility, and they infiltrate Dooku's palace on Serenno. Though they fail to kill the Count, their use of captured Jedi lightsabers leads Dooku to mistakenly believe that the Jedi have tried to kill him. Interested in protection, he requests a new apprentice from Mother Talzin.

When Count Dooku calls upon the Nightsisters seeking a replacement for Ventress, she and her kin seize the opportunity to exact revenge. Ventress visits the far side of Dathomir and the males of the planet seeking the most brutal and powerful warrior among them. Talzin has Asajj secretly select a warrior from the distant Nightbrother village: Savage Opress. With the power of dark magic, Talzin transforms Savage into a hulking warrior ultimately loyal to Asajj. She then delivers Opress to Dooku, where he will serve as his secret Sith apprentice in a plot to overthrow Darth Sidious.

Anakin and Obi-Wan, sent to track down the mysterious figure behind the deaths of several Jedi, soon find themselves on the trail of the monstrous apprentice that Ventress has created: Savage Opress, who has been trained in the ways of the Sith by Dooku. When Opress returns to Count Dooku after an unsuccessful assignment, Ventress strikes. With Opress at her side, she attacks Dooku. Opress' loyalty is fleeting, however, and Dooku and Ventress discover that this new apprentice has a will of his own. When Savage returns to Mother Talzin, she gives him a new task: To seek the Outer Rim for his long-lost brother....