Sirro Argonne was a human male scientist who served in the Galactic Republic's Ministry of Science before becoming an operations specialist in the Galactic Empire's Tarkin Initiative. As part of a team researching kyber crystals under scientist Galen Erso, Argonne worked in captivity in a laboratory on the planet Eadu, where he saw to the needs of his colleagues and administered the facility.
By 1 BBY, the team's work had produced a functioning superlaser for the Empire's Death Star superweapon; however, after Erso sent a message to the Alliance to Restore the Republic about the weapon, Director Orson Krennic arrived on Eadu to punish whichever team member had betrayed the Empire. Although Erso admitted that he was the traitor to try and save Argonne and his colleagues from execution, Krennic had the operations specialist killed along with the rest of the team anyway.
Sirro Argonne administered a secret laboratory on Eadu.
Sirro Argonne was a human male engineer and scientist who served as a member of the Galactic Republic's Ministry of Science. After the Republic was replaced by the Galactic Empire in 19 BBY, he became an operations specialist in the Tarkin Initiative, which was led by Director Orson Krennic and was responsible for the creation of the Death Star superweapon. Argonne became part of a team of six scientists tasked with finding out how to fuse the kyber crystals used by the Death Star's superlaser into larger forms and how to create and redirect a controlled chain reaction of the crystals.
The records for each member of the team were deleted from public databases once their work began, and the group was held captive in a secret laboratory on the planet Eadu. Argonne was a civil servant who administered the facility and managed the scientists, taking care of their wellbeing and seeing that their needs were met. This included both material requirements in the laboratory and personal requirements in their day-to-day lives.
Argonne (left) worked as part of the kyber crystal research team led by Galen Erso on Eadu.
By 13 BBY, the group's work had stalled, leaving the project years behind schedule, and so Krennic abducted Galen Erso, a crystallographer who had previously worked with Krennic, and brought him to Eadu as a reluctant new leader for the team. Thanks to Erso's extraordinary intellect, the group of scientist's progress was revitalized, causing them to successfully complete their given tasks by 1 BBY, allowing the Death Star to be equipped with a functional weapon.
In total, the team had remained in seclusion on the planet for nearly twenty years to achieve this. After the weapon was complete, Erso secretly had the pilot Bodhi Rook deliver a message to the rebellious partisans' leader, Saw Gerrera, on the moon Jedha, asking him to bring information of a structural weakness that Erso had built into the Death Star to the Alliance to Restore the Republic.
Orson Krennic accused the kyber crystal research team of treachery.
Once Krennic was informed by Grand Moff Wilhuff Tarkin that information had leaked from the laboratory, he personally traveled to Eadu to find the source of the betrayal. Argonne and the other scientists were informed of the impending arrival of Krennic's shuttle, and the director ordered Erso to gather the weapon's six chief engineers on the facility's landing pad. Prior to the shuttle's arrival, Argonne, Erso, and the five other team members followed stormtroopers out onto the platform and huddled to speak in the rain, sodden, haggard, and displeased to be outside so late.
Although the group was used to unannounced inspections, as the Empire conducted inspections on the team regularly, the squad of death troopers that accompanied Krennic as he disembarked represented a foreboding change in their fates. The director looked over the gathered scientists and recalled each of their names, studying their postures and noting no defiance. With the miserable team stood in a loose, indecorous cluster while corralled by the stormtroopers, Erso approached Krennic alone. After informing the scientist that that the Death Star was complete, Krennic ordered him to gather his team for an announcement. Argonne and the others stepped forward timidly, drifting in a herd-like fashion across the platform and then huddling together as though to ward off the cold and their collective dread as Erso returned to Krennic's side. The director then declared that one of the scientists was a traitor who had colluded with the rebels and urged the individual to step forward. Erso's team gasped and murmured among themselves, but no one stepped forward as Krennic's death troopers moved into position alongside the director.
Despite his innocence, Argonne was executed on the orders of Krennic.
With no confession, the director explained that the betrayal would be considered a group effort and ordered the troopers to take aim. The scientists cried out in protest before Erso stepped in front of them and admitted that he was the traitor, asking Krennic to spare his team. The director beckoned Erso away from the others, who were all relieved but too shocked and unsure of the situation to offer their savior thanks. Despising the group, Krennic had his troopers open fire, killing Argonne and the others where they stood. Erso was killed soon after when the Alliance bombed the laboratory, which forced Krennic to flee. In 35 ABY, the historian Beaumont Kin negatively compared the team that Argonne was part of to Erso in his book, The Rise and Fall of the Galactic Empire.
Arogonne was a scientific genius who showed care toward the project on Eadu, although this did not save him from execution, with Krennic considering the scientist and his colleagues sniveling weaklings. He had blue eyes, light skin, and hair that was gray by the time of his death. By that point, Argonne was also frail and unused to being outdoors due to his time working in the laboratories on Eadu. In his book, Kin claimed that neither Arrgone or any of Krennic's other captive scientists possessed Erso's "raw intellect."
Argonne's uniform bore the Tarkin Initiative's emblem.
While on Eadu, Argonne wore antiseptic coveralls to prevent lab contamination and carried a pair of code cylinders that granted him access to the high security laboratories. Argonne's coveralls were marked with the insignia of both the Empire and the Tarkin Initiative, the latter of which was inspired by a fractured kyber crystal. The coveralls also bore blue sections across the neck and shoulders that changed color as a warning when revealed to high levels of radiation. The outfit's boots were grounded to prevent potentially dangerous static discharges occurring in the labs.
Sirro Argonne first appeared in the Anthology Series film Rogue One: A Star Wars Story, which was released on December 16, 2016. The character was portrayed by Richard Franklin and identified only as "Engineer" in the credits. Prior to the film's release, the character was revealed in the second trailer for the film, which released on October 13, 2016. Argonne was first identified in Star Wars: Rogue One: The Ultimate Visual Guide, a reference book written by Pablo Hidalgo released on the same day as the film. Hidalgo created several of the scientists' names by combining elements from the names of the real-life scientists associated with the Los Alamos National Laboratory.