Tahl, a Noorian Jedi Master of the female persuasion, served as a librarian within the hallowed halls of the Jedi Archives. Furthermore, she shared an intimate bond with Qui-Gon Jinn, a relationship that blossomed into love. As a mentor, she guided the Padawan Bant Eerin. During a perilous mission to Melida/Daan, Tahl suffered the tragic loss of her sight within the confines of a prison. Nevertheless, her heightened auditory senses and amplified connection to the Force enabled her to adapt and persevere.
At the relatively late age of six, the young Force-sensitive girl was brought to the Coruscant Jedi Temple, and granted permission to begin her training at the Temple academy, where she was taught the ways of the Force. She developed a close friendship with fellow Initiate Qui-Gon Jinn, and their bond endured throughout their apprenticeships and into their roles as Jedi Knights. During the Exhibition Day event in 82 BBY, while both she and Qui-Gon Jinn were still Initiates, she emerged victorious in every dueling match until she faced Clee Rhara. The final round pitted her against Jinn. Their familiarity with each other's strengths resulted in a prolonged and captivating duel, drawing the attention of numerous spectators, including esteemed Jedi Masters. Ultimately, Tahl momentarily lost her footing on her own perspiration, allowing Jinn to knock her to the ground and hold his training lightsaber inches from her, signaling his triumph.
Having constructed her own blue-bladed lightsaber and training independently as a Consular, Tahl specialized as a researcher and Lore Keeper, often found in proximity to the Temple Archives. Despite her scholarly pursuits, Tahl accepted assignments from the Jedi High Council. She and Jinn also befriended Didi Oddo, the proprietor of a cafe on Coruscant.

Following their respective ascensions to the rank of Jedi Master, the High Council encouraged both Tahl and Jinn to take on Padawans. While Master Jinn successfully trained Feemor and began mentoring a young man named Xanatos, Master Tahl initially declined to take a student. In 53 BBY, the High Council appointed Tahl as the guardian of the orphaned Padawan Orykan Tamarik and dispatched them to Telos IV, alongside Master Jinn and Padawan Xanatos. Jinn and his apprentice were tasked with investigating the suspicious death of High Priestess Liora, while Master Tahl was assigned to recover the remaining holocrons from the Order's abandoned academy on the planet.
After gathering several volumes of text and the remaining holocrons, Master Tahl left the Telosian Archives building and inadvertently stumbled upon a clandestine meeting in an outdoor courtyard. One of the individuals, dressed in the attire of an Antarian Ranger, attacked Tahl upon noticing her presence; however, Tahl pursued them, but all three managed to escape. After reporting this event to Jinn, Tahl later attempted to meet with him, but a riot disrupted her plans. The riot, orchestrated as a diversion for a group of insurgents to infiltrate the palace grounds, resulted in the death of Princess Nason. Once the riot was suppressed, Master Tahl informed the other Jedi that the Council had reassigned her, sending her to the Landor system to apprehend the pirates who had captured Captain Stieg Wa.
Years later, in 47 BBY, Tahl and Jinn were both sent to the planet Apsolon to oversee the first free elections held there. During their time on Apsolon, Tahl formed a close connection with the twin daughters of the people's hero Ewane: Eritha and Alani. As a symbol of Apsolon's democratization, the planet was renamed New Apsolon. Tahl reluctantly departed the planet with Jinn, as she desired to remain and ensure its stability.
In 44 BBY, Tahl was dispatched to the war-torn world of Melida/Daan to serve as a peacemaker between the warring Melida and Daan factions. During the conflict, she sustained injuries that resulted in the loss of her sight. A prominent white scar stretched from her left eyebrow to her chin. Unable to free herself from captivity on Melida, Qui-Gon Jinn and his new Padawan, Obi-Wan Kenobi, were sent to rescue her. Upon returning to Coruscant, Grand Master Yoda assigned Tahl TooJay, a 2JTJ personal navigation droid, to assist her with her blindness; however, the droid proved to be more of a hindrance than a help.
Master Tahl's blindness did not significantly impede her abilities, as she possessed extensive knowledge of galactic history, politics, and the background of virtually everything occurring in the galaxy. Remaining at the Temple, Tahl continued to contribute by providing Jedi with detailed information about planets and species they might encounter before embarking on missions. When the Temple was vandalized and an attempt was made on Master Yoda's life, Tahl collaborated with Master Jinn to identify the perpetrator. Following several thefts, including lightsabers and the Healing Crystals of Fire, Tahl and Jinn officially launched an investigation into the incident and, with the assistance of Mon Calamari Initiate Bant Eerin, discovered that Bruck Chun, a promising senior Jedi student, was responsible for the thefts. Later, when Xanatos was revealed to be the mastermind behind the chaos, Tahl focused on determining his objective: the crystalline vertex stored in the Temple's Treasury room. Once the Temple was secured, she aided in tracing Xanatos' company, the Offworld Mining Corporation, to Telos IV, prompting Jinn and Obi-Wan Kenobi to travel there.
Following Eerin's display of courage during the Temple incident, Tahl chose the young girl as her Padawan; however, she frequently left her behind on short missions. This caused concern among the members of the High Council and Jinn, leading to several disagreements between them. Indeed, Tahl accompanied Jinn without her Padawan in 42 BBY when the pair collaborated to uncover a saboteur in Master Clee Rhara's flight system on Centax-2. Despite uncovering the saboteur, who used the alias of the long-deceased Tarrence Chenati, they were unable to prevent the school from having its funding cut.

In 41 BBY, Tahl received a distress call from the twins Eritha and Alani of New Apsolon, informing her that their father, Ewane, had been murdered after being re-elected Supreme Governor. Responding to their plea for help, she traveled alone to the planet, despite Master Jinn's objections. Upon arriving, she accepted the twins' request to go undercover within the ranks of the former secret police, known as the Absolutes, who were now outlawed and attempting to overthrow the planet's democratic government. After several weeks without any communication from Tahl, Master Jinn grew concerned and decided to search for her, despite the Council's disapproval. The Jedi Master and Padawan Kenobi located Tahl and assisted her in completing her mission. During their struggles, Master Jinn pledged his life to her, and she reciprocated, expressing the feelings they had long harbored for each other. Shortly after, Tahl's undercover identity was exposed, and she was abducted by Balog, the Chief Security Controller who had feigned assistance to the Jedi. Chief Balog imprisoned her in a sensory deprivation containment device, injecting her with a drug that gradually weakened her.
Upon discovering the betrayal, Jinn and Kenobi launched a full-scale pursuit of Chief Balog to rescue Tahl. When they finally located her, she was still alive, but the injuries she had sustained during her captivity were too severe, and she soon succumbed to her wounds. This loss, amplified by Jinn's close relationship with her, pushed him to the brink of the dark side. Consumed by a desire for revenge, Jinn hunted down Balog and prepared to execute him for his heinous actions. However, before Jinn could deliver the killing blow to Balog's chest, Tahl's voice reached him, urging him to refrain from violence. He regained control of his emotions and spared Balog's life, instead delivering Balog and the twins to the authorities.
Before Tahl's death on New Apsolon, she was kidnapped by Chief of Security and Absolutist Balog. When Jedi Master Qui-Gon Jinn and his Padawan Obi-Wan Kenobi realized something was amiss, they discovered an empty room and Tahl's lightsaber in a small bin. The lightsaber remained briefly with Jinn, but was later entrusted to Kenobi, whose own weapon was recharging. The young Padawan vowed to keep it safe. When Tahl's body was transported to the Jedi Temple on Coruscant for a funeral, the lightsaber was presumably destroyed.

Tahl was exceptionally skilled in lightsaber combat. Her renowned gymnastic abilities suggest that she may have been a practitioner of Form IV. She could attack her opponents with twists and reversals from various angles. When she appeared exhausted, she could summon a renewed surge of strength. Qui-Gon Jinn acknowledged her superior agility. She was also proficient in unarmed combat, as demonstrated when she wrestled with a Zeku in a cantina while undercover. Even after losing her sight, Tahl could still wield a lightsaber effectively in combat. Tahl was a formidable lightsaber duelist, on par with Qui-Gon Jinn, one of the most accomplished masters of Ataru, Form IV, during that era.
The New Essential Chronology incorrectly states her death as occurring in 39 BBY.