Q9-0, also referred to as Zero or Z, was a protocol droid of the RA-90 series, but with modifications. He operated as a mercenary during the New Republic era. Zero was a member of Ranzar Malk's crew, a group of mercenaries led by Ranzar Malk. The crew included Migs Mayfeld, Burg, Xi'an, and the Mandalorian bounty hunter Din Djarin. Malk tasked them with the rescue of Qin, a prisoner held on the New Republic prison ship called Bothan-5.
During the mission, the team double-crossed Djarin, abandoning him. Zero, who remained on the bounty hunter's gunship, the Razor Crest, discovered Grogu, a youngling whom Djarin had previously saved from a client associated with the Bounty Hunters' Guild. Zero attempted to kill the child, but Djarin, having managed to escape, destroyed him.
For some time, Zero's remains were stored on the Razor Crest. Later, a passenger being transported by Djarin used the droid's vocabulator to communicate with the bounty hunter while they were stranded on the planet Maldo Kreis.
Q9-0, once a protocol droid, transitioned to a criminal career, functioning as a mercenary in the New Republic era. Around 9 ABY, Zero joined a team of mercenaries assembled by Ranzar Malk to rescue Qin, an associate who was being held in prison aboard the New Republic Correctional Transport Bothan-5. The mission was to be led by Migs Mayfeld, a former Imperial sniper. The crew also included Burg, the Devaronian muscle, and Xi'an, a Twi'lek. Malk also enlisted Din Djarin, the Mandalorian bounty hunter, to provide his gunship, the Razor Crest, as it was not registered with either the Galactic Empire or the New Republic.
The mercenaries met at the Roost space station, Malk's base of operations. Mayfeld introduced Djarin to Zero, who inspected the Razor Crest and discovered a garbled holographic message from Greef Karga of the Bounty Hunters' Guild in its communication system. As the team planned their operation, Zero exited the Razor Crest, commenting on several deficiencies of the ship. Zero, chosen to pilot the Razor Crest due to the complex maneuvers needed to land on the prison transport undetected, assured Djarin of his superior reaction time. Once the crew boarded the gunship, Zero piloted it from the station's hangar and jumped to hyperspace.
Sometime later, Zero brought the Razor Crest out of hyperspace near the Dilestri system, approaching Bothan-Five. After cloaking the ship's signal, Zero navigated the Razor Crest along their planned route, his abrupt maneuvers unsettling his passengers. After the Razor Crest landed on the prison transport, the team entered the vessel, while Zero remained aboard the gunship, accessing the transport's systems. Zero guided the team to the control room, disabling the prison ship's surveillance. Upon reaching the control room, Zero hesitated to open the door, sensing an organic presence inside. The crew entered anyway, finding Lant Davan, a New Republic soldier, who was killed by Xi'an after a brief confrontation. As Davan died, he activated a tracker, and Zero informed the crew of an incoming New Republic distress signal targeting their location.
The crew located Qin's cell and freed him. However, the mercenaries betrayed Djarin, trapping him in the cell and leaving him to face the approaching New Republic forces. Meanwhile, Zero continued to examine the Razor Crest's communications, viewing the entirety of Karga's message, which mentioned a delivery to a client. Djarin managed to escape the cell, and Zero alerted Mayfeld to the situation. The Razor Crest's communications then failed, preventing the crew and Zero from contacting each other. Zero then noticed Grogu, the youngling mentioned in Karga's message, whom Djarin had rescued after delivering him to the Client. Zero, interpreting the message's mention of a bounty on Grogu as a priority, decided to kill the child.
Zero grabbed his blaster rifle and began searching for Grogu, who was hiding elsewhere on the ship. While Zero was searching, Djarin defeated the other mercenaries, confining them in a cell on Bothan-Five. Zero located Grogu in a concealed compartment, aiming his rifle at him. However, Djarin boarded the Razor Crest and shot Zero from behind, destroying the protocol droid before he could fire.
Djarin kept Zero's shattered remains aboard the Razor Crest, storing them in a heap within the ship's cargo hold. After the Razor Crest was damaged and became trapped inside an ice cave on the planet Maldo Kreis while Djarin was transporting "Frog Lady" and her spawn to the moon of Trask, Frog Lady tried to communicate the urgency of her mission, but the Mandalorian couldn't understand her language. While Djarin slept in the hold of the wrecked Razor Crest, Frog Lady bypassed Zero's security protocols to utilize the droid's vocabulator for communication.
The bounty hunter awoke to Zero's voice and pointed his blaster at the wreckage, believing the droid himself was speaking. Using Zero's vocabulator, Frog Lady reassured Djarin, explaining that her family lineage would end if her eggs weren't brought to safety. Although Djarin was alarmed by her use of the droid due to the danger Zero had posed, Frog Lady convinced him to repair the damaged Razor Crest. They eventually escaped the cave, though the hold of the vessel was left open to space during their journey to Trask. The Razor Crest crashed into the ocean upon landing on Trask and was later repaired, but the vessel and most of Djarin's possessions were destroyed by turbolaser fire from Moff Gideon's light cruiser above Tython.
Q9-0, known as Zero and Z by his fellow mercenaries, was a protocol droid with modified programming, allowing for precise timing. Being a droid, Q9-0 possessed a faster reaction time and greater intelligence compared to organic beings, a point he frequently emphasized. This gave him an advantage when piloting, enabling him to perform maneuvers that others could not. Zero could operate a starship by directly connecting to its systems via a socket, eliminating the need to physically manipulate the controls. During Qin's rescue, Zero sliced into the transport's systems, disabling its security measures.
Ranzar Malk described Zero's programming as "rough." The droid often boasted to Din Djarin about his superiority over organic beings, and Malk assured Djarin that Zero was the best despite his programming. The droid also openly criticized the condition of the Razor Crest, pointing out its flaws and questioning why its use was necessary. Q9-0 stood at 1.8 meters, or 5 feet 11 inches, tall and had a bipedal form, with two arms and two legs. His plating was dark gray, and he had two large, bug-like photoreceptors behind silver, mirrored domes. He also had a recharge port in the center of his torso and a communications antenna on top of his head. Zero spoke with a calm, authoritative voice. Security protocols were also integrated into the droid's systems.
Zero carried an EE-3 carbine rifle and wore several equipment pouches on his torso, some containing blaster repair tools. He also had a vambrace as part of the plating on his wrist. Ranzar Malk owned several starships at his space station, which Q9-0 was familiar with piloting. During Qin's rescue, Zero piloted the Razor Crest, Djarin's gunship.
Q9-0 debuted in Chapter 6 of The Mandalorian, the 2019 television series, which was broadcast on December 13, 2019. Richard Ayoade provided the character's voice, and Christopher Bartlett performed the physical role. Although referred to only as Zero in the episode, Q9-0's full name was revealed in the credits. Bartlett stated that Q9-0 was his favorite character to portray out of his various appearances in the series. Brian Matyas created concept art of Ranzar Malk's crew, including Q9-0.
A droid with a similar appearance to Q9-0, also portrayed by Bartlett, previously appeared in the third chapter of the series, released on November 22, 2019, although no connection was established between the two droids. This droid participates in the Bounty Hunters' Guild's attempt to prevent Djarin from escaping with Grogu, an event Q9-0 is unaware of in Chapter 6.