Qui-Gon Jinn's early career as a Jedi was marked by one tremendous failure, which took many years for the Jedi Master to overcome. After successfully training one Padawan to Jedi Knight status, Qui-Gon agreed to take a Jedi hopeful named Xanatos as his next apprentice. The son of Crion, the wealthiest man on the planet Telos, Xanatos was born with a high midi-chlorian count. After Qui-Gon discovered the boy, Crion reluctantly allowed Qui-Gon to take Xantos to Coruscant for training.
Xanatos proved a difficult student who used his high birth in attempts to impress other students at the Jedi Temple. Despite his obvious flaws, Xanatos proved a dedicated student who always sought to learn more about the ways of the Force and please his Master. Eventually, Yoda deemed Xanatos ready for a final test, he asked Qui-Gon and his Padawan to return to Telos, where Crion implored his son to join forces with him in an attempt to take control of the planet. Xanatos agreed to his father's request, and Qui-Gon soon found himself battling his student in a dangerous civil war on Telos.
Qui-Gon was eventually forced to kill Crion in battle. Xanatos, who witnessed his father's death, immediately attacked his master. Qui-Gon defeated Xanatos, but could not bear to kill the boy. Xanatos fled and disappeared. Haunted by Xanatos' betrayal and his own failure, Qui-Gon refused to take another padawan learner.
Years later, Qui-Gon Jinn encountered Xanatos again. The former Padawan, who had established himself as the secret leader of the Offworld Corporation, attempted to trap Qui-Gon on Tatooine. Qui-Gon disrupted Xanatos' plot with the aid of Obi-Wan Kenobi, a Jedi hopeful whom Qui-Gon had previously refused to take as his Padawan learner, despite Jedi Master Yoda's urgings. Xanatos escaped from the Jedi, but Qui-Gon had overcome his sense of failure and agreed to train Obi-Wan. In the years that followed, they would embark on many adventures together throughout the galaxy.
Eventually, Mace Windu sent Qui-Gon and Obi-Wan to settle a trade dispute in the Naboo system. Aboard a Trade Federation droid control ship, the Jedi were attacked, but they managed to escape. Soon after, Qui-Gon rescued a strange Gungan named Jar Jar Binks, who swore a life debt to the Jedi. Obi-Wan and Qui-Gon then traveled to the city of Theed, where they liberated Queen Amidala and vowed to deliver her safely to Coruscant.
During the trip to Coruscant, the Queen and her entourage were force to stop on Tatooine, where Qui-Gon discovered a boy named Anakin Skywalker. He immediately sensed the boy's strong connnection to the Force and ultimately liberated Anakin from slavery. He also confronted a strange warrior, who Qui-Gon suspected to be a Sith Lord. After barely escaping the encouter with his life, Qui-Gon traveled to Coruscant to present Anakin to the Jedi Council.
Unfortunately, the Jedi Coucil on Coruscant refused to allow Qui-Gon to train the boy, as his future seemed clouded and uncertain. Qui-Gon nevertheless kept Anakin by his side, even as he made his last, fateful voyage to wartorn Naboo.
On Naboo, Qui-Gon and Obi-Wan confronted the Sith Lord Darth Maul. Maul proved a deadly and cunning apponent. When fighting alongside Obi-Wan, Qui-Gon could fend off the Sith Lord's attacks, but eventually master and apprentice became separated. During this brief moment, Maul pressed his advantage, wearing down Qui-Gon's defenses and ultimately killing the Jedi Master. Obi-Wan soon defeated Maul, but nothing could save Qui-Gon. With his dying breath, the Jedi Master asked Obi-Wan to train Anakin, a request that Kenobi readily accepted. Three days later, the Jedi Master was cremated at a funeral attended by numerous mourners, including Anakin, Obi-Wan, Jar Jar, and the Jedi Council members.