The infected clones subsequently attacked and killed the frigate's two pilots, before going after the Jedi. Offee was eventually captured and infected after she and Tano split up, leaving the Togruta Padawan as the only un-infested individual still alive on board. After getting in contact with her master Anakin Skywalker, Tano was eventually informed that the worms, coming from a hot planet, were vulnerable to the cold, and ruptured the coolant systems to flood the ship and bring the temperature down, incapacitating the clones. Offee, being Mirialan, was less affected, but Tano managed to incapacitate her and destroy the worm controlling her after the frigate dropped out of hyperspace. Offee and the surviving clones made a full recovery.
During the Clone Wars, the Galactic Republic was forced to invade the planet Geonosis a second time as the native Geonosians had restarted production of battle droids. After the planet's subjugation, during the hunt for fleeing Geonosian leader Archduke Poggle the Lesser, Jedi Master Luminara Unduli and clone trooper Buzz tracked him to the Progate Temple, a structure that had already been destroyed and had apparently contained nothing of interest. Shortly after their arrival in the midst of a heavy sandstorm, Unduli was captured and Buzz was killed by undead Geonosians animated by brain worms controlled by the Geonosian queen Karina the Great. After the storm was over, Obi-Wan Kenobi, Anakin Skywalker, Commander Cody and a squad of clone troopers arrived at the temple and descended into the catacombs in an attempt to locate Unduli and Poggle. Unduli was nearly infected by a brain worm before her rescue, with Kenobi attempting to take it back for study before Skywalker destroyed it. Karina was killed when her underground chamber was collapsed onto her.
Afterwards, the Jedi were preparing to take Poggle to Coruscant for trial when Jedi General Ki-Adi-Mundi arrived with word of a complication: although Mace Windu and his forces had taken Dantooine, they had suffered losses and were in desperate need of medical supplies, which could be obtained from the Ord Cestus medical station. As Ord Cestus was a considerable ways from the conventional route between Geonosis and Coruscant, Skywalker suggested that his and Unduli's Padawans, Ahsoka Tano and Barriss Offee, be sent to collect the supplies. Clone trooper unit Tango Company was also dispatched on the mission. However, several of the company's troopers had taken the opportunity for an open-air nap, and a surviving brain worm infected the sleeping trooper Scythe. After company lieutenant Trap had awoken his men, no one noticed anything was wrong with Scythe, with Pulsar mockingly inviting him back to the "land of the living" when he finally got up. When Tango Company boarded the Pelta-class frigate TB-73 with Tano and Offee, Scythe's backpack was full of brain worm eggs.
After TB-73 had entered hyperspace, most of those onboard the ship went to sleep, excluding the pilots and a few other clones. However, Tano found herself unable to fall asleep, and eventually persuaded Offee to accompany her to the commissary for a late-night snack. Scythe, under the influence of the worm, took advantage of the situation to infect all of the sleeping clones with the worms as well. The infected troopers of Tango Company subsequently attacked the bridge and, catching the pilots by surprise, shot them to death.
Tano and Offee, discussing the war and their respective masters over food, found out there was a situation when troopers Ox and Edge entered the commissary and almost immediately attacked them. After subduing the troopers by telekinetically throwing them against the wall, Tano and Offee held Trap and Havoc at lightsaber-point when they entered the room. Both troopers claimed not to know what was going on either, and Havoc was left to guard Ox and Edge while Trap accompanied Tano and Offee to the bridge. When they arrived, however, the security shields were activated on Scythe's orders, preventing them from reaching the bridge. At this point, Trap was revealed to have been infected as well, dropping the façade of normal behavior and attacking the Jedi. Tano and Offee realized what was wrong with him when the worm partially emerged from Trap's mouth, and Offee killed him in self-defense by igniting her lightsaber through his torso.
The clones of Tango Company became infected by the worms.
Tano and Offee, sneaking through the frigate, were aware they had to somehow get word of the situation to their masters and the Republic. Entering a cargo hold, they witnessed one clone trooper who had avoided the initial infection get overpowered by his brothers and taken over by a worm. The two Jedi were subsequently attacked by the clones, deflecting fire before escaping into an air vent. Offee suggested to Tano that they had to split up, with her going to the engine room to try and stop the ship while Tano went to the aft communications room to try and signal for help. Tano was reluctant, but agreed after Offee pointed out they didn't have much choice. However, when she reached the engine room, Offee fell into an ambush set by Scythe and the other troopers, and was subsequently infected by a brain worm.
Onboard the Jedi Cruiser transporting Poggle, Skywalker, Unduli, Kenobi, and Mundi became aware there was something wrong when TB-73 failed to check in on schedule. Although Skywalker wanted to search for his apprentice immediately, the older Jedi pointed out that it was imperative that they get the Separatist leader to Coruscant as soon as possible, although they did agree that the situation was concerning. Skywalker ordered Clone Captain Rex to watch out for any transmissions from Tano while he and the other Jedi interrogated Poggle.
Offee attacked her friend after she was infected.
When Tano reached TB-73s aft comm room, she was able to contact Master Kit Fisto at the Ord Cestus medical station and inform him of the situation, and Fisto insisted that she get the ship to the medical station in order to contain the infection and help the infected. Tano then contacted Skywalker and Rex and informed them of what was going on aboard the frigate, but was subsequently attacked by the infected Offee. When Skywalker informed the other Jedi, they attempted to find a solution, but their interrogation of Poggle had failed to find any answers. Skywalker proceeded to go interrogate Poggle again by himself, resorting to brutal tactics, including Force choking, since mind tricks did not work on Geonosians. He came back to the other Jedi with the answer that the worms were incapacitated by the cold, since Geonosis was a hot planet, while avoiding answers to how he had managed to get the information out of Poggle.
Skywalker contacted Tano with the information of the worms' weakness, and ordered her to rupture the frigate's coolant systems. Navigating the ship through the air vents, Tano made her way to the coolant chamber, avoiding the clones and running from Offee. After flooding the ship's vents with coolant, Tano made her way directly to the bridge, just as the ship exited hyperspace. Master Fisto dispatched two spacetugs to use their tractor beams to slow down the frigate so it could safely dock with the medical station. Tano was then attacked on the bridge by Offee, who, being Mirialan, was less affected by the cold than the clone troopers. After a brief fight, which caused the frigate to list to one side, Tano managed to subdue Offee, who asked Tano to kill her. When Offee's worm emerged from her mouth as she attacked again, Tano instead killed the worm.
Kit Fisto recovers the two Padawans.
The two tugs slowed TB-73 and allowed it to safely dock at the medical station. Upon boarding, Fisto and his troops found Tano and Offee in the bridge. Tano, shivering, told him she was there to pick up the medical supplies, and the Nautolan Jedi Master reassured her that she didn't have to. When Tano woke up onboard the medical station, Skywalker had arrived, and he told her she had done well, and assuaged her concerns about Offee's request for death. Tano was assured that Offee and the infected clones were all making a full recovery. Deducing how the infection had begun, regulations were enacted for Republic troops occupying Geonosis not to sleep out in the open to prevent any further incidents.
The skirmish aboard TB-73 first appeared in the Star Wars: The Clone Wars second season episode "Brain Invaders."
- Star Wars Helmet Collection 41
- Star Wars Encyclopedia of Starfighters and Other Vehicles
- "The Zombies of the Galaxy" — Star Wars - The Official Magazine 95