Tamu Dree, known as Cadet 542-146, was a human male who served as a cadet within the ranks of the Galactic Empire. He was the twin brother of Lyttan.
To escape starvation on Boiyuh, Tamu Dree enlisted in the Imperial Military alongside his twin brother, Lyttan Dree.
The Carida Academy served as the training ground for both Tamu and his brother. They witnessed an altercation between fellow cadet Han Solo and another cadet, Beilert Valance.
When Solo, having been released from solitary confinement and returning to duty, joined Tamu and his brother as they reviewed the leaderboard rankings of the cadets, Tamu collected a bet from his brother, who had anticipated Solo's demise. Valance then approached the group and initiated a fight with Solo, resulting in Solo being knocked to the floor. Following this confrontation, Tamu collected another bet from Kanina Nico regarding Solo's survival.
During a training exercise in the air, Valance's fighter struck Tamu's TIE fighter, causing it to lose control. Tamu lost consciousness, and his TIE fighter was set on a collision course with the energy shield protecting the training grounds. Solo intervened by destroying the shield generators with his own fighter, ejecting from his ship to board Tamu's TIE fighter, and successfully landing it. After landing, Tamu received medical attention and was subsequently confined to the brig along with the rest of Solo's squad.
Later, Tamu, along with his brother, Solo, and Nico, received orders to Imperial Cruiser 07200823 to transport TIE fighters and their respective pilots to a rendezvous point with a Star Destroyer. Nico assumed command and assigned Tamu to navigation duties. After the TIE fighters were delivered, Tamu informed Nico that Solo's modifications had improved the engines' efficiency, putting them a day ahead of schedule. Solo then suggested a visit to a nearby Pantolomin cruiser for entertainment. Once aboard, Tamu and the others enjoyed the ship's hospitality. While participating in a gambling game, Tamu encountered a female named Ylra. He then married her, but their ceremony was interrupted when the rest of the squad apprehended him while escaping Pjolan and his gang. Upon their return to Carida, Tamu and the others were reassigned to flight duty.
Tamu, as a member of Carida Squadron, was deployed to Qhulosk to engage the natives in combat. Upon arrival, he inspected the modifications Solo had made to his TIE fighter and suggested to his brother that they implement similar changes to their own ships. He was then dispatched, along with the rest of his squadron, to attack Howlan. He shadowed Valance during a strafing run that successfully destroyed the shield generators and cannons defending the city. After Qhuloskian fighters shot down Valance, Tamu returned to base. When Solo decided to launch a rescue mission, Tamu joined him on a speeder bike.
He traveled to Holowan with his squadron, but falling debris from bombing runs by TIE bombers destroyed his speeder bike. Tamu managed to jump onto his brother's bike and escape to safety. Tamu wanted to go directly to Valance's location, but his squadmates stopped him because of the Qhuloskian soldiers in the area. They reached Valance's crash site, and Tamu administered first aid to his injuries. On the way back to base, the group encountered a large group of Qhuloskians, and Solo attempted to bluff their way out of the situation. They were rescued by a group of Ghulars who revealed that the Empire was invading Qhulosk to extract farium for starship construction. When Solo devised a plan to fake Nico's death in action so she could return to her home planet before the Empire enslaved her boyfriend, Tamu agreed to participate in the deception. He was unsure of her chances of evading the Empire but offered her his support.
Back at the base, Tamu was present when Valance was informed that his injuries would prevent him from flying again. He also informed Solo that he was being transferred to the medics because the Empire was impressed with his field medical skills. He hoped to be stationed at a base near his wife's location, but admitted he was unsure if they were still married.
Later, Tamu received a call from his brother, who was serving in the elite 204th Imperial Fighter Wing. Tamu told his brother that his wife and children had relocated from the city to reduce their risk. They discussed the progress of the war and reminisced about their past.