Jyala Haydenn served the Galactic Empire as a human lieutenant and Imperial officer. She was stationed aboard the Executor, Darth Vader's flagship, during the Galactic Civil War. During her service, she lost her left eye, resulting in a scar on the left side of her face that remained uncovered by synth skin. In 3 ABY, Haydenn was present with the Executor above the planet Jekara, shortly after the Auction for Han Solo organized by Crimson Dawn. When bounty hunters Boba Fett and Beilert Valance infiltrated the Executor to retrieve the carbonite-encased Han Solo, Fett betrayed Valance, leaving him for dead. Valance eventually reached the ships seventeenth level, where he encountered a cadet named Venn. A midshipman informed Haydenn, who was on the bridge of the Executor, about Valance's presence. Haydenn instructed the midshipman to eliminate the hostile by venting the compartment, despite the cadet's presence. Haydenn declared that the cadet's sacrifice for the Empire would be remembered, and threatened the midshipman with the same fate via an air lock if they questioned her orders again.
After the midshipman complied with Haydenn's command, they reported that the camera feed from the level was lost. The midshipman then informed the lieutenant that the intruder was identified as a former Imperial soldier, whose file contained information beyond the midshipman's rank to access. Intrigued, Haydenn expressed that Vader should be informed of this development. Later, Haydenn abandoned the Empire and assisted in restoring Valance's memories during the scourge of the droids.