|“||I am Sai Sircu. Remember that name, for it is the herald of your impending deaths!||„|
|~ Sai Sircu, to two Jedi|
Sai Sircu is the main antagonist of Star Wars: The Clone Wars: Jedi Alliance. She is the leader of a faction of Nightsisters. She formed an alliance with Count Dooku and the Confederacy of Independent Systems in order to destroy the Jedi Order.
Sai Sircu, head of a group of Nightsisters who formed an alliance with the Separatists during the Clone Wars to overthrow the Jedi Order they hated. The Nightsister should help their allies build a super weapon powered by lightsaber crystals, the battle cruiser Devastation. After his sister Yansu Grjak attacked the Sedawan, a Jedi transport ship, two Jedi followed the trail of Jedi Master Luminara Unduli, who was kidnapped during the conflict, to Dathomir. There they managed to free Unduli after a lightsaber fight with Sircu. Although the Nightsister was able to use the Force to incapacitate a group of clone troopers shortly thereafter, another fight with the Jedi forced Dathomir to flee. She then went to the devastation.
When the weapon was finished, she took part in a conversation with Count Dooku, his student Asajj Ventress, and Darth Sidious, who was added via a hologram, in which the allies demanded a demonstration of the weapon. When Dooku then proposed that Sircu's homeworld Dathomir be the first target, but Sircu, angered over the sudden betrayel, blasted Dooku and Ventress with dark energy, forcing them out of the bridge. She now had command of the ship and set the ship on course for Coruscant. However, six Jedi managed to infiltrate the devastation. In an attempt to prevent the super weapon from being used against Coruscant, she was killed fighting Mace Windu and Anakin Skywalker. The Jedi managed to destroy the Devastation.