Gillam Tarturi was a Human male. He was the son of Senator Berm Tarturi, who represented the planet Andara and, ostensibly, the entire Andaran system within the Galactic Senate. This occurred in the declining years of the Galactic Republic, prior to the outbreak of the Clone Wars.
Gillam's physical appearance, particularly his height and build, bore a resemblance to Anakin Skywalker. He served as the leader of a group of young mercenaries undergoing training at Andara's prestigious Leadership School. The other members of his squad included Marit Dice, Rolai Frac, Tulah, Hurana, and Ze.
Gillam possessed a persuasive and charismatic personality, which he utilized to convince the others to join his team. He felt neglected by his father, believing that the Senator prioritized his official duties over his son. During an operation on Ieria, he and his associates feigned acceptance of Padawan Anakin Skywalker into their ranks. Subsequently, he plotted to assassinate Skywalker, intending to frame his father for the kidnapping and murder. However, Anakin, acting alone, triumphed over all six mercenaries. Upon the arrival of the Jedi and security forces, Gilliam pretended to be innocent, falsely claiming that the Ierians had abducted him. Nevertheless, Ferus Olin, whom he underestimated as a mere inquisitive student, had uncovered a datapad detailing his scheme. As a consequence, the entire squad faced expulsion from the Leadership School. Skywalker, along with Siri Tachi, Ferus Olin, and Obi-Wan Kenobi, transported them to Coruscant for interrogation, aiming to resolve the web of deceit, treachery, and illegal activities that had plagued the group.