Garil Dox, a male Human, functioned as a gunner aboard the Imperial Star Destroyer known as the Reprisal during the Galactic Civil War era.
Following the obliteration of his home planet, Lieutenant Dox experienced a profound crisis of faith in the Empire. He maintained his duties at his station until the day Darth Vader himself came to the Reprisal searching for Rebels. Vader's objective was to seize and interrogate rebels to discover the location of the Rebel fleet. Dox resolved to prevent this outcome at all costs.
Vader instructed Commander Demmings to launch attacks on the rebels and secure prisoners, but three attempts resulted in no survivors. Initially, Vader attributed these failures to Demmings' lack of skill, but he soon discerned that Dox was intentionally ensuring that no one survived.
However, unbeknownst to Dox, Vader and Demmings eventually deduced his Alderaanian lineage. They then manipulated him by presenting an Alderaanian refugee camp on Ejolus, as a rebel base, which became his third target. Upon learning this truth, Dox was devastated by the realization that he had wiped out what may have been the last remaining Alderaanians in the galaxy, and he pleaded with Vader to end his life.
Vader, however, had different plans for Dox and dispatched him to an Imperial labor camp.