Yorr was a captain within the Imperial Navy and a human who piloted the ST 321, which was a Lambda-class T-4a shuttle. In the year 4 ABY, Yorr, along with Colonel Jendon, utilized the shuttle to convey the Sith Lord Darth Vader from the Imperial II-class Star Destroyer called Avenger to the Death Star II superweapon. At that time, the latter was still being constructed within the Endor system.
Later, during the Battle of Endor, Yorr piloted a newly developed version of the TIE/d "Defender" Multi-Role Starfighter. In this battle, the Alliance to Restore the Republic were tricked by the Galactic Emperor Sheev Palpatine into launching an assault against the Death Star. Yorr engaged in combat against the rebels in the skies above the moon Endor, but ultimately, the Alliance succeeded in destroying the Death Star.

As a human, Yorr was a captain of the Galactic Empire's navy, specifically in the officer corps. He commanded ST 321, the Lambda-class T-4a shuttle belonging to the Sith Lord Darth Vader. In 4 ABY, Yorr and Colonel [Jendon] (/article/jendon) jointly piloted the shuttle as it departed from the hangar of the [Avenger, the Imperial II-class Star Destroyer stationed in the Endor system. Their mission was to transport Vader to the Empire's still-under-construction Death Star II superweapon, which was being built above the moon Endor. Two TIE/ln space superiority starfighters accompanied the shuttle, also departing from the hangar.
Yorr then used comms to contact the Death Star, informing them of the shuttle's approach. He identified the vessel's code clearance as blue and requested that the Death Star's shields be lowered for landing. Jad Bean, a flight controller aboard the Death Star, responded, instructing Yorr to wait until the shuttle's code transmission was received. Upon arrival, Bean cleared ST 321 for landing and deactivated a section of the shield. Yorr and Jendon then maneuvered the shuttle to one of the Death Star's hangars, where their TIE escort detached. ST 321 then retracted its wings and landed inside. Vader then exited the shuttle to meet with Moff Tiaan Jerjerrod to discuss the progress of the station's construction.

Galactic Emperor Sheev Palpatine soon arrived on the Death Star as well. He intended to use his presence and the station's incomplete state as a lure to draw the fleet of the Alliance to Restore the Republic into attacking the Death Star. His goal was to utilize its fully operational superlaser to destroy them, thus bringing an end to the Galactic Civil War. The Alliance fell into the trap, and upon the arrival of their fleet, they were surrounded by Imperial forces and engaged in battle. During this conflict, Yorr piloted a TIE/d "Defender" Multi-Role Starfighter as part of the Starfighter Corps, flying alongside a TIE/IN interceptor.
Palpatine, wanting to make a statement, ordered only the Empire's starfighters to engage the rebels. The Imperial capital ships were ordered to hold their fire so that the Death Star's superweapon could target the Alliance's primary vessels. Yorr exchanged fire with the enemy above Endor, but ultimately, rebel forces on the moon below managed to deactivate the Death Star's shield generator, allowing the rebel fleet to destroy the Death Star and secure a victory over the Empire.
While piloting ST 321, Yorr was attired in a black Imperial officer's uniform, complete with an Imperial kepi bearing an officer's disk. During the Battle of Endor, the pilot operated a new version of the TIE/d "Defender" that featured secret Chiss engineering. It also included ion cannons and computer-assisted controls.

Yorr's initial appearance was in Star Wars: Episode VI Return of the Jedi, a film from the original trilogy that premiered on March 25, 1983. The character was physically portrayed by actor Jasper Jacob in an uncredited role; the script simply referred to him as "shuttle captain." The scenes within the shuttle cockpit were filmed on Stage 6 at Elstree Studios between March 24 and March 31, 1982. Jacob spent two days filming under the direction of Richard Marquand. He recorded more dialogue than was ultimately used, including lines about Vader's impatience. He also found it challenging to memorize his lines, which necessitated numerous takes. Yorr's lines were later dubbed by Colin Kitchens.
In current Star Wars canon, Yorr's name was first revealed in a preview for the 2024 Battle Over Endor Scenario Pack for Atomic Mass Games' Star Wars: X-Wing Second Edition board game. Within the Star Wars Legends continuity, Yorr appeared before the film's release in its novelization, which featured additional dialogue for Yorr similar to the cut lines that Jacob remembered. This novel was written by James Kahn and released on May 12, 1983. The character was first identified in Legends in 2000 on a card in the "Death Star II Limited" set for the Star Wars Customizable Card Game published by Decipher.