Allie would not serve on the Council long before her demise on the planet Saleucami during the waning hours of the Clone Wars. Having received the command to execute Order 66 from the Sith Lord Darth Sidious, Clone Marshal Commander Neyo and a clone trooper lieutenant opened fire on their general from their speeder bikes, killing her instantly.
Stass Allie was born on Tholoth prior to the Separatist Crisis. She was the cousin of Jedi Master Adi Gallia, who was born into a high-ranking diplomatic family on Coruscant. Allie was found to be Force-sensitive and brought to the Jedi Temple on Coruscant to start her Jedi training. She specialised in the art of healing, which would become an invaluable resource in the bloody years-long clone war. Like her cousin, Allie would also become a consular and rising star diplomat. She was eventually granted the title of Jedi Master and became a member of the Circle of Jedi Healers, in addition to serving as an overseer of the Medical Corps.
Allie was present in Supreme Chancellor Palpatine's office along with other senators and Jedi as the issue of whether Palpatine should take emergency powers was debated.
After the Jedi Council received word that Senator Padmé Amidala, Jedi Anakin Skywalker and Obi-Wan Kenobi had been captured by the the leaders of the Confederacy of Independent Systems and the Geonosians resulting in a sentence to death, Stass Allie was recruited and joined Mace Windu's Jedi Strike team sent to rescue them. She and her fellow Jedi fought valiantly in the Petranaki Arena against the Separatist Droid Army. Most of the Jedi were killed in the ensuing battle, though Allie and others managed to survive long enough for the new clone army to arrive, which had arrived to escort the remaining Jedi off the planet or to lead the wider battle on the planet aboard Republic gunships. She and Bultar Swan, who she had been fighting back to back with, boarded the same gunship and were brought to the desert plain where the battle had spread to. The two shared a nod before they both charged forward to continue fighting the Separatist Droid Army.
Over the course of the Clone Wars, Allie continued to hone her healing skills even while deployed as a Jedi General, though her diplomatic skills were tested as the Separatist threat loomed.
When Savage Opress kills Adi Gallia during a fierce battle, Stass Allie was invited to take her cousin's place on the Jedi High Council. Allie gratefully accepted and followed Gallia's footsteps. Due to her new responsibilities, Allie frequently appeared at Council meetings on Coruscant as a hologram from the different Republic worlds she was assigned to.
By 19 BBY, Council member Stass Allie was present in the infamous session when Anakin Skywalker was granted a seat as the Supreme Chancellor's representative member and denied Masterhood status and later seen in a hologram meeting when Yoda was sent to Kashyyyk and Obi-Wan Kenobi to Utapau.
As leader of the 91st Mobile Reconnaissance Corps, Allie took part in siege of the planet Saleucami during the Outer Rim Sieges. During this momentous time, Kenobi would kill Grievous on Utapau, Yoda would lead the defence of Kashyyyk, and Anakin would betray the Jedi leading to his fall to the dark side and the commencement of Order 66 and the Jedi Purge. Allie was accompanied by the 91st Mobile Reconnaissance Corps led by the clone commander Neyo. Unknown to Allie or any of the other Jedi, the clones had all been created with inhibitor chips, forcing them to comply with the execution of Order 66 by performing the extermination of all the Jedi across the galaxy.
As the Order was played on their comlinks from Supreme Chancellor Palpatine, Allie, along with Neyo and a Clone Lieutenant, were patrolling the bleak and barren landscape of the war-torn planet on BARC speeders during the mop up operation. She was completely caught off guard as Neyo and his wingman fell back and fired upon her speeder without hesitation. She was killed as the speeder exploded into pieces.
Stass Allie was a focused, stern, young looking woman with a desire to help others. She had indigo eyes and dark skin contrasted with green highlights around her eyes, hands and forehead. As a member of the Tholothian species, Allie had a scaled cranium from which fleshy white tendrils drooped from her head.
Stass Allie was talented in lightsaber combat, having been trained to knighthood. Her sword skills were grimly tested when she survived the opening battle of the Clone Wars on Geonosis along with 28 others out of the original 212 . While her swordsmanship was impressive, her talent for Force healing was more so. She passed down this skill to other Jedi, including Barriss Offee. Like like her cousin, Stass Allie was extensively trained in diplomacy and advisory skills, but when the Clone Wars called for the jedi to serve as generals, she realised that she was also a skilled warrior.
Stass Allie possessed a green-bladed lightsaber that she used during the Battle of Geonosis. She also wore tall tan travel boots, a utility belt, a white undershirt with white pants, a grey tunic topped with dark robes. Her head was adorned with a Tholoth headdress consisting of a brown fabric rim framing her face laced with interlocking thin chains which adorned her scaled cranium.
The creation of the character of Stass Allie is in many ways a retcon that took place prior to the release of any Attack of the Clones products. The filmmaker intended to use the majority of Jedi High Council members in the film's climactic Battle of Geonosis; however, because most of the film was shot in Australia instead of England, local model Lily Nyamwasa replaced Gin Clarke, who portrayed Adi Gallia in Star Wars: Episode I The Phantom Menace. She filmed all of her scenes wearing Adi Gallia's costume, but the filmmakers eventually realized that she looked too different from Clarke's version of the character, so they created a new character for the film, who became known as Stass Allie.
After the death of Adi Gallia in Star Wars: The Clone Wars, in January 2013 the supervising director for the series, Dave Filoni, stated that the animation team had created a character model for Stass Allie and that she was to appear in the show in a later season. This never happened, however.
Revenge of the Sith depicts Anakin Skywalker to be the one to utter the line "A partial message was intercepted in a diplomatic packet from the chairman of Utapau." However, Star Wars: The Prequel Trilogy – A Graphic Novel mistakenly depicts Allie as the one to have said the line. The reference booklet "Yoda and Other Users of the Force" states that Allie only arrived on Saleucami after its battle had concluded during the Outer Rim Sieges, but other sources establish she was part of the Siege of Saleucami proper. As such, "Yoda and Other Users of the Force" must be incorrect.