Malorum, a Human male, stands out as a key figure from the early days of the Galactic Empire. As a founding member of the Inquisitorius, he rose to become its inaugural Grand Inquisitor following the establishment of the Empire.
Malorum's imposing stature was accentuated by a dark maroon robe, reminiscent of those favored by Emperor Palpatine. Though never inducted into the Jedi Order, Malorum possessed a slight sensitivity to the Force.
Initially, Malorum served as an operative within Imperial Intelligence. Alongside Director Armand Isard, he visited the Jedi Temple in the aftermath of Order 66. It was there that he witnessed a hologram of Emperor Palpatine addressing Anakin Skywalker as Lord Vader. Consequently, Malorum became one of the few individuals within the Empire – along with Prince Xizor two decades later – privy to Vader's true identity, a secret unknown to both Vader and Palpatine themselves.
This incident led to Palpatine selecting Malorum from relative obscurity, revealing his identity as a Sith, and entrusting him with the leadership of the Inquisitorius. He was aided by a subordinate Inquisitor named Hydra. Subsequently, Malorum dedicated himself to uncovering all possible information about Skywalker, employing bribes, surveillance, and investigations into past events. He discovered that Skywalker was the father of Senator Amidala's (presumed dead) child. He hired Boba Fett to conduct inquiries on Naboo and within the asteroid field of Polis Massa, seeking details about the deceased Padmé Amidala. Driven by personal ambition, Malorum aimed to gain favor with Vader while simultaneously gathering intelligence to orchestrate his downfall. His investigations on Vader's behalf earned him the moniker of Vader's "pet." However, Malorum harbored aspirations of supplanting Vader as the Emperor's apprentice, with the ultimate goal of becoming Emperor himself.
Eventually, Malorum was reassigned to Bellassa, where he assumed the role of chief of security, responsible for training Imperial Security Bureau agents on the planet. He developed an obsession with capturing the fugitive ex-Jedi Ferus Olin, enlisting the aid of bounty hunters like Boba Fett and D'harhan to suppress the Rebel uprising on Bellassa.
The ghost of Jedi Master Qui-Gon Jinn then directed his former Padawan, Master Obi-Wan Kenobi, to assist Olin, knowing that this would lead Kenobi to discover Malorum's investigation of Polis Massa and the crucial need to stop Malorum before the Skywalker twins could be found. Olin successfully escaped Bellassa with Kenobi's help. For a time, Kenobi overestimated Malorum's influence, mistakenly believing him to be the mastermind behind the Inquisitorius operations in Acherin. Although Kenobi soon returned to his exile on Tatooine, he tasked Olin with addressing the threat posed by Malorum.
Malorum was then assigned to the Jedi Temple on Coruscant. He established his office in the former living quarters of Jedi Master Yoda. While at the Jedi Temple, he received a visit from Darth Vader. Malorum shared all his knowledge of Polis Massa with Vader, hoping to impress him. However, upon hearing the name of the location, Vader became enraged by the reminder of his deceased wife, nearly killing Malorum by force choking him. The unexpected discovery of an intruder in the Temple led to Vader releasing Malorum so that the Inquisitor could track him, but to Vader's surprise, Malorum failed.
Subsequently, Malorum planted a sleeper bomb within the Temple, intending to destroy it and discredit Vader in the eyes of the Emperor. However, the bomb was deactivated by Ferus Olin, Trever Flume, and Fy-Tor-Ana. When stormtroopers captured Ferus, they interrogated him, demanding the name of the Jedi he had encountered on Bellassa. Ferus refused to cooperate, even under threat of execution.
Malorum then dispatched Ferus to the prison planet of Dontamo, later ordering his execution. He subsequently traveled to Naboo to gather more information about Amidala. Malorum's time on Naboo proved frustrating, with Queen Apailana and other Naboo officials refusing to provide him with direct answers – he found the Queen's attitude particularly irritating. Malorum then murdered Ryoo Thule after deducing that Amidala's child was still alive, but was stopped by Ferus Olin before he could report this information. Malorum and Ferus engaged in a fierce lightsaber duel on Naboo. Ultimately, Malorum lost his grip on his lightsaber and fell to his death into the Naboo power generator.
Despite Olin's jamming of planetary communications, Palpatine was immediately aware of Malorum's demise and contacted Olin to commend him for his success and extend an offer, before Olin could report to Kenobi.
Malorum had received basic training in lightsaber combat, wielding a red-bladed weapon. Ferus Olin described his fighting style as relying on agility but lacking grace, possessing strength but lacking the skill to use it effectively, and being fueled by aggression as his primary source of power.
Ferus described Malorum as having the Dark Side humming within him as he drew upon his anger. Malorum attempted to use telekinetic abilities and physical augmentation to catch his lightsaber and safely jump over the pit at the same time but lost control and was unsuccessful. The attempt costing Malorum's life. Ferus stated the failure to jump over the pit and telekinetically retrieve the lightsaber was due to Malorum straining and making an elemental mistake of an early year Jedi student. Being blinded by the need of the moment, allowing emotion to get in the way, and allowing the fear of being disgraced by losing his lightsaber to cloud his mind.