|Chronological and political information|
- "Thought we were saving the Republic. We brought Tarnis the prototype. He turned on us. Killed everyone."
- ―Jonkan, moments before his death
Jonkan worked as a part of the Republic Superweapon initiative, working on the prototype for the Planet Prison superweapon with a team of four other scientists. During the Cold War, Jonkan's superior, Doctor Eli Tarnis, informed the team that the Jedi Order was planning to shut the project down, and ordered that the prototype be moved into the territory of the Justicar Brigade.
Convinced that they would be acting in the Republic's best interests, Jonkan and his team re-located the weapon as instructed, but upon arrival, Tarnis revealed himself to be a Sith Lord and murdered the science team, mortally wounding Jonkan. Tarnis absconded with the prototype, and a [[Jedi Knight]t arrived in Justicar territory to investigate.
Jonkan struggled to give the details of the encounter with Tarnis, but when the Knight offered to take him to a medcenter, he refused, stating there was no time left. He told the Knight to use the Planet Prison's energy signature to track it's location, as when activated, the weapon would be vulnerable to heat scans. He urged the Jedi to hurry before his injuries finally killed him.