Force psychosis was a specific mental ailment affecting several young Jedi in the period after the Second Galactic Civil War. This condition triggered a cognitive decline within the affected individual's mind, manifesting as intense paranoia and the conviction that everyone they knew—excluding others similarly afflicted—was an imposter. The Jedi Order detained several affected individuals for observation, discovering that those with the psychosis could use unusual Force abilities previously demonstrated by Jedi Knight Jacen Solo, skills the afflicted Jedi should not have known. Conversely, another affected Knight, Bazel Warv, exhibited the capacity to manipulate matter density, a power never shown by Solo.
Earlier in their lives, members of the Mind Walkers—a community of Force-attuned individuals residing at Sinkhole Station, a space-based installation within the Maw—had faced and endured comparable symptoms. However, after living at the station and journeying to a plane of the Force called beyond shadows, their paranoia transformed into a belief that only the Force held true reality. In time, Luke Skywalker and his son, Ben, formed an alliance with a faction of Sith and embarked on a quest to the Maw with the intention of destroying Abeloth, a dark side entity suspected of instigating the psychosis. Despite the Sith's attempt to double-cross the Jedi and force Abeloth into servitude, Skywalker prevailed and defeated Abeloth, resulting in the immediate healing of those affected by the psychosis. However, as the Sith and Jedi investigated Abeloth, they discovered she had survived and escaped.
When High Lord Sarasu Taalon of the Sith immersed himself in the Pool of Knowledge, he started transforming into a being like Abeloth, until he was killed by Sith apprentice Vestara Khai, although Abeloth once again evaded capture. Given her continued existence, Luke believed that keeping her weakened was the only factor preventing the return of the psychotic Knights' mental states. However, following the rescue of Valin and Jysella Horn from carbonite, they still suffered from the psychosis. Another battle with Abeloth liberated the Horn siblings from her influence. As Abeloth regained strength, however, she managed to sway several Sith to betray their Tribe and join her.
The dark side being Abeloth manipulated the minds of Force-sensitive individuals to lure them to her in the Maw, with the goal of feeding on their life force to amplify her own power. She employed her abilities to convince the Force-sensitives that only the Force held true reality, leading them to perceive anyone not under her influence as an impostor. She exerted this control dating back to at least the era of the Galactic Republic and Old Jedi Order, though initially infrequently, and the situation went unnoticed by the Jedi.
Jedi Knight Seff Hellin fell under Abeloth's influence and became the first Jedi whose strange behavior was noted by the New Jedi Order. Later, Jedi Knight Valin Horn contracted the psychosis and was captured by his father, Corran, and mother, Mirax. He later escaped, only to be recaptured by the Jedi Order following an extensive search. The Galactic Federation of Free Alliances determined that Horn posed too great a threat to be held in a conventional prison, leading to his encasement in carbonite and placement within the Armand Isard Correctional Facility. Hellin discovered Horn's presence there and attempted to free him, but was instead captured by Darkmeld—an organization established by Jedi Knight Jaina Solo to oppose Chief of State Natasi Daala's anti-Jedi policies. Jedi Master Cilghal then initiated a clandestine study of the disease in Hellin at the Jedi Temple on Coruscant. Shortly thereafter, Horn's sister Jysella also developed the psychosis, and following a duel with fellow Knights Bazel Warv and Yaqeel Saav'etu, she was apprehended by Galactic Alliance Security forces. Natua Wan, a Falleen Knight, also succumbed to Abeloth's influence. She was subsequently apprehended by Jedi Knights Radd Minker, Jaina Solo, and Leia Organa Solo, and brought to the Temple for study.
Upon examining Hellin's brain, Cilghal realized he was experiencing waking dreams. It was also found that several of the affected Knights could use rare Force abilities that Jacen Solo had possessed, abilities that the Knights themselves could not have learned. Further research revealed that the disease's symptoms lessened when the victim was cut off or isolated from the Force for extended periods. This discovery led some healers to posit that the disease might be transmitted through the Force itself. Cilghal noted that all those afflicted had been stationed on Shelter in the Maw during the Yuuzhan Vong War.
After being isolated within a Force bubble created by an ysalamir, Hellin began to show signs of recovery. Meanwhile, Saav'etu and Warv also contracted the disease, though Warv briefly recognized Organa Solo as not being an impostor. These two Knights were captured by Organa Solo, her daughter Jaina, Head of State Jagged Fel of the Imperial Remnant, and Han Solo. A Galactic Alliance Security force under the command of Captain Atar attempted to arrest the two psychotic Jedi, but Fel and the Solos ensured their safety. It was also noted that Warv could alter the density of matter, a power Solo never exhibited. Later, Warv, Saav'etu, Wan, and Hellin were smuggled offworld to Shedu Maad in the Hapes Cluster to avoid conviction by the Galactic Alliance. A group of Jedi and reporters also gained access to the blockhouse where the Horn siblings were held. They found the Horns' carbonite blocks suspended over a fish tank in the executive offices of the building, which garnered public sympathy for the Jedi.
Meanwhile, exiled Jedi Grand Master Luke Skywalker and his son, Ben Skywalker, had begun a quest to understand the reasons behind Darth Caedus' fall to the dark side of the Force. During their travels, they encountered Jedi Knight Qwallo Mode—who had disappeared a year prior and was presumed dead—floating in the vacuum of space without a vac suit. Their journey then led them to Sinkhole Station, a space station in the Maw, home to the Mind Walkers. There, they found Mode and learned he was also afflicted with the psychosis, though he recognized the Skywalkers and did not see them as impostors. The Jedi interacted with the Mind Walkers, who could separate their minds from their bodies to travel in a Force realm called beyond shadows. Luke Skywalker entered this realm as his Mind Walker guides showed him the locations they had taken Caedus during his visit. Ben grew concerned for his father and convinced the Mind Walker Rhondi Tremaine to take him beyond shadows as well. After finding his father, they saw Abeloth—whom the Mind Walkers knew as the "Lady in the Mists"—in the Mists of Forgetfulness. They intended to approach her to learn her true nature, but after speaking with Caedus' spirit in the Lake of Apparitions, they decided to return to their physical bodies. This decision proved wise—the Jedi were ambushed by a strike team of Sith from the Lost Tribe on Kesh. They defeated the Sith, and Ben later theorized that Abeloth was causing the illness.
Soon after, a Chev Jedi Knight, Sothais Saar, developed the psychosis while reporting to Wynn Dorvan, Daala's personal aide, in the Senate Building. After escaping to the Senate Plaza, Saar was confronted by Cilghal, who captured him before Coruscant Security Forces could arrive. The Security Forces tried to force the Jedi to hand Saar over, but the Jedi refused. In response, Daala sent a task force of Mandalorians to attack the Jedi Temple.
Later, the Sith confronted the Skywalkers on Dathomir and allied with the Jedi to eliminate Abeloth, though the Sith intended to betray and kill the Jedi and force Abeloth to serve them. The allied forces first traveled to Klatooine to replenish supplies before beginning their mission. There, the Force-sensitive Dyon Stadd succumbed to the psychosis while planet-side with Ben Skywalker and the Sith apprentice Vestara Khai. He was captured and taken into custody aboard the Jade Shadow. Meanwhile, more Jedi on Coruscant began developing the psychosis, including the Human Jedi Kunor Bann and Turi Altamik, prompting Cilghal to write a report expressing her concern about the rapidly increasing number of affected Jedi.
While Bann was captured inside the Jedi Temple, Altamik escaped and led a chase caught on holocam by journalist Javis Tyrr before being captured by the Jedi. The Galactic Alliance demanded custody of Altamik and Saar, and when the Jedi refused, Daala ordered a Mandalorian siege of the Jedi Temple. The trapped Jedi began to run low on supplies, including medications for their psychotic captives. However, Leia Solo devised a plan to use the Force to compel rodents into service, using them to sneak supplies into the Jedi Temple.
Meanwhile, as the Sith and Jedi continued their mission, they discovered that Sinkhole Station was destroyed, and suspected that Abeloth, previously confined there, had grown powerful enough to break free. They went to a planet in the Maw where Khai and the strike team that attacked the Jedi at Sinkhole Station had met Abeloth. There, the Skywalkers realized the locations they had seen beyond shadows matched real locations on the planet. As Skywalker and three Sith tried and failed to find Abeloth by traveling beyond shadows, Khai pretended to help Stadd by letting him escape the Jade Shadow, but secretly placed a homing beacon on him. The Jedi and Sith followed him to Abeloth's cave, where they found she had drained his life force and fled deeper into the cave, leaving Stadd for dead. After encountering her, Stadd finally realized Abeloth was not who she claimed to be. Though he still felt surrounded by impostors, he understood it was due to her influence and thus a lie. The Jedi and Sith found Abeloth, but she appeared as Callista Ming and pretended to be Skywalker's long-lost lover. He soon realized it was a lie and attacked her. During the fight, Skywalker seemingly killed Abeloth, ending her induced psychosis and instantly curing all affected beings. Cilghal reported the sudden cure of Saar, Altamik, and Bann to interim Grand Master Kenth Hamner.
Saar and Altamik were presented to Daala in the Fellowship Plaza and examined by Doctor Thalleus Tharn under Daala's orders. They were declared sane, and the siege was lifted. However, the Sith and Jedi on Abeloth's planet discovered she had not died. As they searched for her, Sith High Lord Sarasu Taalon bathed in the Pool of Knowledge and began transforming into a being like Abeloth. The Sith and Jedi alliance ended, and the Skywalkers and Khai tracked Abeloth to the moon Pydyr. They learned she was living among the Fallanassi, and Luke found she was using the White Current to create the illusion of a planetary plague, fooling all the Sith and Jedi except Luke Skywalker.
Meanwhile, conflict arose within the Jedi Order on Coruscant. The Jedi Council wanted to quickly rescue the Horns and aid the Skywalkers by sending a strike team of StealthXs, but Hamner wanted to negotiate with Daala for the Horns and delay the launch, as he had agreed with Admiral Nek Bwua'tu during the Temple siege to wait for the Admiral's word to send the StealthXs in exchange for the Alliance navy's cooperation with the Jedi. However, Bwua'tu had been attacked by assassins, leaving him in a coma. The Jedi Masters grew frustrated with Hamner's inaction, and upon learning of his deal with Bwua'tu—made without consulting them—they removed him as acting Grand Master and decided to launch the StealthXs. Hamner tried to stop the launch but failed, falling to his death from a catwalk in the hangar. Afterward, Master Saba Sebatyne was unanimously voted to replace him as interim Grand Master.
On Pydyr, Khai called for reinforcements, and three shuttles of Sith arrived with Taalon. Taalon decided not to kill the Jedi yet, as they might still be useful, but in the ensuing confrontation with Abeloth, Skywalker killed another of Abeloth's bodies—the Fallanassi Akanah Norand Goss Pell—and Taalon was killed by Khai to prevent him from becoming another Abeloth. However, when the other Sith learned Khai had killed him, unaware of the reason, she was forced to flee with the Skywalkers under cover of the arriving StealthX wing, continuing to chase Abeloth. Luke suspected their constant pressure on Abeloth, keeping her weak, was causing her to lose control over the Jedi Knights' minds, and thus did not want to lose her.
Meanwhile, the rescue of the Horns succeeded, and they were brought back to the Jedi Temple to be freed from carbonite. Though they seemed normal upon reawakening, it was a ruse—the Horn siblings still had the psychosis. By pretending to be fully recovered, the Horn siblings managed to be assigned missions, giving them a chance to escape Coruscant. After contacting journalist Kandra Nilitz, they traveled to Nam Chorios, where Abeloth was hiding. There, they abandoned Nilitz, and Jysella commandeered one of the planet's defending gun platforms while Valin located Abeloth on the surface. However, Khai and the Skywalkers were also searching for Abeloth on Nam Chorios, and they found and severely weakened her, freeing the Horn siblings from their psychosis. The Skywalkers, Khai, and the Horns escaped while a Jedi StealthX wing defeated Sith forces in orbit.
Soon afterward, however, Sith Saber Gavar Khai, Vestara Khai's father, and several other Sith defected from the Sith Tribe to join Abeloth's forces, as her influence over him grew stronger. Khai was later killed in a duel with his daughter, and during the duel, she realized he had fallen under Abeloth's influence.
The psychosis's symptoms included widespread paranoia, coupled with the conviction that everyone had been replaced by impostors, except for other similarly affected individuals. Moreover, infected Jedi could instinctively use rare Force powers they did not possess before contracting the psychosis. Several Mind Walkers experienced similar symptoms before joining the group at Sinkhole Station, where they came to believe that only the Force was real. This belief lessened the psychotic beings' paranoia—Mode and the other Mind Walkers did not believe the Skywalkers were impostors. Another symptom was the belief that Abeloth and other affected beings were the only truthful, trustworthy beings in the galaxy. While affected, Stadd felt Abeloth desired him and saw her as beautiful until he truly encountered her, when she began to drain his life force and he realized her influence had been a lie. Later, when Gavar Khai fell under Abeloth's influence, he was convinced to desert the Lost Tribe even though Abeloth had just killed his wife. He later claimed that losing his wife and even his daughter did not matter, as he could replace them. The irrationalities he showed during his duel against his daughter revealed to her that he was no longer the same person he had been.
- Mind Walker Feryl [2] †
- Mind Walker and former Jedi Knight Seek Ryontarr [2] †
- Mind Walker Rhondi Tremaine [2] †
- Mind Walker Rolund Tremaine [2] †
- Mind Walker and former Jedi Knight Qwallo Mode [2] †
- Jedi Knight Seff Hellin [5]
- Jedi Knight Valin Horn [5]
- Jedi Knight Jysella Horn [6]
- Jedi Knight Natua Wan [6] †
- Jedi Knight Yaqeel Saav'etu [2]
- Jedi Knight Bazel Warv [2] †
- Jedi Knight Sothais Saar [4]
- Jedi Knight Kunor Bann [1]
- Jedi Knight Turi Altamik [1]
- Force-sensitive Dyon Stadd [1] †
- Sith Saber Gavar Khai [3] †
Force psychosis made its initial brief appearance in the novel Millennium Falcon. It subsequently played a central role in the Fate of the Jedi series.
Force psychosis bears similarities to the real-world condition known as Capgras delusion.