In the year 2 BBY, a clandestine operation saw rebels Morad Sumar, Kanan Jarrus, Ezra Bridger, and the astromech droid Chopper secretly enter the Imperial Armory Complex situated on Lothal. Their covert assignment occurred simultaneously with an inspection conducted by Grand Admiral Thrawn, who was there to investigate the unusually frequent acts of sabotage plaguing the manufacturing facility. Despite the tragic death of Morad, who was killed by Thrawn during a demonstration of a 614-AvA speeder bike that went awry, the Spectres successfully acquired the schematics for a prototype TIE fighter. Their escape from the factory was aided by Imperial Security Bureau Agent Kallus, who had become disillusioned with the Empire and was now providing intelligence to the rebellion. The attack led Thrawn to the deduction that a traitor existed within the ranks of the Galactic Empire.
During the Age of the Empire, the Galactic Empire established a significant military installation on the world of Lothal. Through collaboration with Governor Arihnda Pryce, Lothal was designated as the central hub for Imperial operations within the Lothal sector. Following his escape from an Imperial detention facility in 3 BBY, the former governor of Lothal, Ryder Azadi, established a rebel cell at a stone circle located in Lothal's wilderness. This group was composed of Lothal residents who were dissatisfied with the Empire's policies, including farmers Morad and Marida Sumar, as well as the Ithorian bartender named Jho.
By the time 2 BBY arrived, Ryder's resistance group had initiated a campaign focused on sabotaging Imperial vehicles at the Imperial Armory Complex, which served as a manufacturing center for armored walkers, 614-AvA speeder bikes, and TIE fighters utilized by the Imperial Military. This resulted in a surge of accidents, injuries, and deaths among Imperial military personnel. Eventually, Imperial High Command noticed the suspicious rate of mishaps involving vehicles produced at the Lothal factory and dispatched Grand Admiral Thrawn to conduct an investigation.
Concurrently, the rebel group Phoenix Cell made the decision to neutralize the Imperial Armory Complex on Lothal. Lacking a presence on Lothal, they reached out to Ryder's resistance cell for assistance. Phoenix Squadron also received intelligence from Fulcrum indicating that the Empire was developing a new, classified weapon at the facility. This Fulcrum operative was later revealed to be the Imperial Security Bureau Agent Alexsandr Kallus, who had grown sympathetic to the rebels after his encounter with the Lasat rebel Garazeb Orrelios on Bahryn. He had also aided the Mandalorian Sabine Wren in her escape from Skystrike Academy alongside two defecting cadets during an undercover mission. Phoenix Leader Hera Syndulla sent her crewmembers Kanan Jarrus, Ezra Bridger, and Chopper to infiltrate the factory in order to gather information on this new secret weapon.
The crew of the Ghost met with Ryder outside Capital City using his speeder. After fighting off an AT-DP walker and two speeder bikes, the rebels escaped to Ryder's stone circle encampment in Lothal's wilderness. There, the rebels discussed their information and plans. The former farmer Morad, who now worked as a factory worker at the Imperial Armory Complex, agreed to help Kanan, Ezra, and Chopper infiltrate the factory. Morad informed the rebels that the Empire had tightened security around Section A2 and suspected the plans for the secret weapon were being stored there.
Morad, Kanan, Ezra and Chopper gained access to the Imperial Armory Complex by disguising themselves as factory workers and an Imperial astromech droid, respectively. Their arrival coincided with an Imperial inspection led personally by Grand Admiral Thrawn. In the presence of Governor Arihnda Pryce, Agent Kallus, and Lieutenant Yogar Lyste, Thrawn delivered a speech criticizing the factory workers for the high number of accidents caused by vehicles manufactured at their factory. As a demonstration, Thrawn forced Morad to demonstrate the last 614-AvA speeder bike he had inspected. Using a simulator, Thrawn accelerated the speeder to its maximum speed. This caused the faulty engine to overheat and explode, destroying the bike and killing Morad.
Following Morad's death, Thrawn warned the workers that they would be responsible for personally testing the vehicles they built. Thrawn then ordered his subordinates to impose a lockdown on the factory and screen every worker. Kanan tried to contact Ryder to warn Hera, but found that the Imperials were jamming their signals. With a security screening underway, Kanan and Ezra realized they had to escape and got Chopper to stage a distraction by destroying a speeder bike.
After escaping the security screening, the two rebels proceeded on their mission to reach Section A2. Ezra warned Kanan that they would have to get new disguises since the workers were on lockdown. Fortuitously, they ran into a stormtrooper and scout trooper, who the two Jedi promptly knocked out and stripped of their uniforms. After losing contact with Kanan, Ezra and Morad, Ryder contacted Hera via hologram and informed her about the new Imperial officer. Hera recognized the officer as Grand Admiral Thrawn, whom she had encountered earlier on Ryloth. Ryder planned to launch a diversionary attack on the factory's east gate to distract Thrawn.
Ezra, Kanan, and Chopper soon managed to reach Section A2 in their disguises. However, the chamber was guarded by stormtroopers who would only admit R4 courier droids carrying clearance codes. Thrawn had ordered anyone not carrying his personal code in Section A2 to be terminated on sight. Continuing his inspection, Thrawn forced another factory worker to admit that he had inspected an AT-DP on display. Thrawn had Agent Kallus make the walker step forward. When that walker collapsed, he ordered the man's arrest.
Later, Thrawn was informed of the missing workers by Lieutenant Lyste, and realized that rebel infiltrators had breached the factory. Lyste also told Thrawn that the workers' uniforms had been found, leading him to conclude that the rebels had already found new disguises. He ordered Agent Kallus to secure Section A2.
Despite Thrawn's stringent precautions, the Ghost crew managed to elude the Imperial guards by incapacitating a courier droid and stealing its clearance code. This allowed Chopper to enter the room and download the design database. Before Chopper could finish his work, Kanan and Ezra were confronted by a stormtrooper corporal and his men, who demanded to know why they were outside their perimeter. Kanan claimed that they were on guard duty.
While the corporal did not believe him, Chopper emerged from the room at that moment. Ezra swiftly claimed that he and Kanan had mistaken Section A2 for Section B17, and the three rebels walked away, only to turn a corner and find Lyste giving stormtroopers orders about establishing a lockdown. They were pursued by the corporal and his troopers as they fled in the other direction. Arriving at a bank of turbolifts, Kanan hit the call button but got no response. He suggested that things might get "messy," but a lift opened to reveal Agent Kallus, who ordered the disguised rebels inside, supposedly to help him secure the perimeter. Inside, Kallus revealed that he knew who the rebels were. Following a brief fistfight, Kallus revealed that he was Fulcrum, managing to convince the rebels of this by using his code phrase and citing his past encounters with their comrades Zeb and Sabine. Kanan and Ezra were still suspicious, but solicited Kallus' help in reaching a communications station so that they could transmit a signal on their comlinks to Ryder. Kallus obliged, and the rebels managed to storm a communications station and stun the stormtroopers and Imperial officer stationed there.
Once there, Chopper unlocked Kanan and Ezra's comlinks, not needing Kallus' offered access codes. Kanan managed to contact Ryder, who revealed that he was preparing to launch an attack on the east gate. Kallus advised the rebels to escape on an AT-DP walker in the east gate's hangar bay. To conceal Kallus' dealings with the rebels, Ezra hurled the ISB agent through a glass monitor board to make it look like he had put up a fight against them. By this stage, Thrawn had studied the history and art of the crew of the Ghost. After linking the missing factory workers with the unregistered C1-series astromech droid known as Chopper, Thrawn deduced that the rebels were being helped by someone within the Imperial hierarchy.
At that point, Ryder and his rebel cell launched an attack on the east gate, damaging at least one Imperial Troop Transport. Reasoning that Ryder's forces had attacked in order to create a distraction for the rebels to escape, Thrawn decided to play the rebels' game. In response to Ryder's attack, Lieutenant Lyste sent the two AT-AT walkers 271 and 414 to engage the insurgents. Thrawn allowed Lyste to dispatch reinforcements in order to lure Ezra and Kanan into a trap. The crew of the Ghost took the bait and rode out on the AT-DP Walker 216 under the pretext of helping the AT-ATs fight the rebel attackers.
The AT-ATs asked what Walker 216 was doing at the east gate, and Ezra claimed that they were reinforcements. Studying the rebels' escape patterns, Thrawn realized the rebels had stolen an AT-DP walker and ordered the AT-AT pilots to destroy the walker the rebels had hijacked. Ezra managed to maneuver his walker under one of the AT-ATs. However, the AT-AT pilots aboard proceeded to use their heavy walker to crush the rebels' smaller walker. Ezra and Kanan used their lightsabers to cut themselves and Chopper out of the doomed transport and board the AT-AT walker. After dispatching the pilots, their hijacked AT-AT walker was hit by a rocket fired by Marida, the wife of the late Morad Sumar. She and Ryder had witnessed the hijacked AT-DP exploding, and believed Kanan and Ezra to be dead. Kanan and Ezra managed to fire on and destroy the other AT-AT before their walker collapsed. Exiting the AT-AT walker, the three rebels fled with Ryder, Jho, and Marida on two landspeeders.
Upon returning to Ryder's secret location, Ezra, Kanan, and Ryder transmitted the data from Chopper's memory to Sabine, who successfully decrypted it. The information revealed that the Empire was developing a new prototype TIE Interceptor equipped with a deflector shield. The rebels were concerned that mass production of this fighter by the Empire would pose a significant threat to the rebellion and its pilots. Ezra and Kanan also informed Hera, Sabine, and Zeb about Kallus' assistance in their escape. The other Spectres were shocked, and Zeb deduced that he must have "accidentally" recruited Kallus back on Bahryn. Distrusting him, Hera decided that they would wait and see what kind of game their new ally might be playing.
Back on Lothal, Thrawn shared his suspicion with Governor Pryce and Agent Kallus that the Empire had a mole among their ranks who was aiding the rebellion. When Governor Pryce suggested questioning all Imperial personnel, Thrawn advised against a mass crackdown. Instead, he proposed setting up a trap for the informant in order to turn that individual into an Imperial "asset." Thrawn wanted to wait for the spy to make their next move. Feigning loyalty, Kallus commended the Admiral for his "flawless" strategy.
The main narrative of the Star Wars Rebels episode "An Inside Man," which premiered on Disney XD on December 3, 2016, revolves around the infiltration of the Imperial Armory Complex. The episode also included the TIE Defender, a starfighter that had previously appeared in various Star Wars Legends materials.