The quest to find Darth Sidious represented a significant undertaking by the Jedi Order. Their objective was to locate and capture the elusive Sith Lord who had managed to evade the grasp of the Galactic Republic for more than ten years. This endeavor commenced on Cato Neimoidia in the aftermath of a particular battle. This battle revealed the existence of a mechno-chair, presenting the Jedi with a potential lead in their pursuit of the Sith Lord. This mechno-chair gave the Jedi an opportunity to follow a path that ultimately led them to the Sith's hidden base, situated within the dilapidated LiMerge Building located in Coruscant's industrial sector.
However, Sidious quickly became aware of the Jedi's pursuit and decided to exploit this situation to his advantage. He instructed his apprentice, Count Dooku, to misdirect the Jedi's investigation and eliminate two potentially incriminating individuals who could provide further clues to the Jedi. These efforts proved unsuccessful, and Jedi Masters Mace Windu and Shaak Ti initiated an investigation of the LiMerge Building. Anticipating this, Sidious, in coordination with General Grievous, orchestrated a surprise assault on Coruscant in an attempt to divert the Jedi's attention. While this tactic achieved partial success in diverting the Jedi, Aurek Team confronted Sidious and his droid forces. During this encounter, Sidious revealed his identity to one officer before the officer succumbed to his injuries. This event brought the investigation into Sidious to a halt, safeguarding his secret and leading Grand Master Yoda to believe that Sidious had escaped off-world.
The presence of the Sith Order was initially revealed to the Jedi Order on Tatooine and subsequently on Naboo in 32 BBY. However, for the next decade, they remained concealed, failing to resurface as the Jedi had anticipated. During this period, the Order questioned whether the Sith Lord eliminated on Naboo was a master or an apprentice, and they debated the possibility of a "Second Sith". Count Dooku, who was himself later revealed to be a Sith Lord, disclosed to the captured Jedi Knight Obi-Wan Kenobi on Geonosis in 22 BBY that a Sith named Darth Sidious exerted influence over numerous senators within the Galactic Senate. This was the first instance in which the Jedi became aware of Sidious by name.
Throughout the Clone Wars, the Jedi were unable to obtain further information regarding Sidious, despite their suspicions that the "Second Sith" might be a member of the inner circle advising the Supreme Chancellor, with individuals such as Sate Pestage and Mas Amedda being considered as potential suspects.
In the final month before the war's conclusion, the Galactic Republic achieved a crucial victory on Cato Neimoidia, but they failed to capture the leaders of the Trade Federation, Nute Gunray and Rune Haako. However, this apparent failure transformed into a significant success when the Republic acquired a mechno-chair that provided them with their first glimpse of Darth Sidious. The Jedi High Council determined that the time had come to locate and capture the elusive Sith Lord, viewing the mechno-chair as a promising initial step in that direction.
The Council dispatched Jedi Master Obi-Wan Kenobi and Jedi Knight Anakin Skywalker to pursue any leads that might guide them to Sidious. Initially, they decided to keep the investigation within the Jedi Order, refraining from reporting it to the Supreme Chancellor. However, the battle at Belderone compelled Grand Master Yoda and Mace Windu to inform Palpatine about their investigation. Palpatine, acting as Sidious, summoned his apprentice Count Dooku to Coruscant, where they discussed the Jedi's initiative. Sidious tasked Dooku with diverting the Jedi's efforts to prevent them from discovering his trail, while also ordering him to eliminate any loose ends that could lead the Jedi to him and his hidden base.
Kenobi and Skywalker journeyed to Charros IV to meet with the Xi Char, bringing along TC-16, a former Trade Federation protocol droid (captured on Cato Neimoidia), to serve as a translator. Their purpose was to question the Xi Char regarding engravings found on the mechno-chair belonging to a Xi Charrian named t'laalak-s'lalak-t'th'ak. He answered their questions, but became agitated and attempted to escape. The commotion led to the Jedi pursuing the Xi Charrian through a warehouse, causing significant disruptions before he was apprehended. He answered their questions while the Xi Charrian prelate arrived and demanded that Kenobi and Skywalker leave due to the disruptions caused. The Jedi learnt that the chair came to Charros IV from Escarte.
The Jedi arrived at Escarte, but the authorities denied them permission to land. However, Skywalker harassed the patrol ships to land to the point where a tractor beam guided their ship to the landing platform. The base's captain arrived to arrest them but en route reveals that he is the Republic Intelligence agent Travale. Kenobi and Skywalker are thrown into a cell with the Bith Thal K'sar (the one who worked on the chair) but Travale's cover is blown and he too is incarcerated.
But Travale manages to cause a power failure that enables the four to escape. Kenobi and Travale go to deactivate the tractor beam to allow their ship to leave the planet while Skywalker and K'sar get to the ship. Skywalker further interrogates K'sar who revealed there were two chairs and that the one he worked on in 33 BBY contained a hyperwave transceiver and a holoprojector. K'sar elaborated that Darth Sidious himself contacted him and once the chair was completed never heard from the Sith Lord again. It was at that stage that K'sar realized that his recent death sentence was Sidious attempting to cover up his tracks. K'sar also told Skywalker that the chair he worked on ended up on an experimental craft and told them that the Jedi could find the pilot in hiding on Naos III.
Darth Sidious hoped to set up a trap on Naos III and instructed Dooku to hire assassins to kill Fa'ale Leh and Kenobi also. The Jedi arrived on the planet and searched several cantinas looking for a trace of Leh. The two managed to locate the Lethan who assumed the name "Genne" in order to escape those pursuing her since she revealed to the Jedi that those who worked on the ship were all killed off not long after she delivered the ship to the client. Leh was aware that K'sar was the sole survivor besides herself.
But assassins cornered the three before she could answer additional questions. Leh's right lek was lost during the escape but she managed to tell the Jedi that she delivered the ship to a building in Coruscant's industrial district. Leh also told them that she delivered it to someone who looked like a Jedi but was not because their lightsaber was different.
The failure on Naos III prompted Sidious to order General Grievous to accelerate their plans to attack Coruscant as the last-ditch attempt to divert the Jedi. He likewise instructed Dooku to act as bait on Tythe to divert Skywalker and Kenobi while he would deal with those hunting him down on Coruscant.
Mace Windu and Shaak Ti led Aurek Team and several Padawans into the LiMerge Building with Captain Dyne leading the investigation. His assessment of the building confirmed that Dooku met with Sidious in the building and it led the group to a turbolift that in turn led them to tunnels leading them towards the direction of the Senate District. Examining those tunnels led them to a repulsorlift speeder bike that would lead them to 500 Republica but a sudden jolt in the building forced the Jedi to leave to investigate and to learn that Coruscant was under attack. The clones continued their search and found a door in the tunnel with one sentient behind it and droids as well.
The following commotion saw the entire team slain save for Dyne who in his final moments looked upon Sidious to see that he was in fact Supreme Chancellor Palpatine.
The Jedi were unsuccessful in their mission to locate and apprehend the Dark Lord, and the clones who continued the search beneath Coruscant were killed in their attempt to capture the Sith Lord. The Council initially believed that Sidious had fled off-world, but they did not discover until approximately a week later that Sidious was, in fact, Supreme Chancellor Palpatine. This revelation prompted a Jedi attempt to arrest the Sith Lord. The four Jedi were each killed, and the Dark Lord successfully executed his decade-long plan to convert Anakin Skywalker to the dark side as his third Sith apprentice, Darth Vader.