Tann Gella was a female Twi'lek from the Rutian species, originating from the planet of Ryloth. She shared a twin sister relationship with Ann Gella. By the time 32 BBY rolled around, both sisters had experienced enslaved conditions before being acquired as possessions by Sebulba, a Dug podracer. Sebulba had purchased them from Jabba Desilijic Tiure, a Hutt crime lord. During that year, the twins accompanied Sebulba to the planet Tatooine.
The Dug had plans to participate in the renowned Boonta Eve Classic podrace, which was to be held just outside the Mos Espa spaceport. Before the commencement of the race, the twins provided assistance to Sebulba in his preparations. While he was situated with his podracer within the hangar of the Mos Espa Grand Arena, Tann gave him a shoulder massage while Ann tended to his toenails. The Dug found the Twi'leks' services pleasing and considered them attractive, although the massage was actually a ruse for guarding his vehicle from race officials and rival pilots. Tann was characterized by her blue skin and brown eyes. While on Tatooine, the twins were seen wearing matching yellow net outfits paired with a gray headpiece and a silver collar.
The character of Tann Gella was brought to life by the actress Nishan Hindes in the movie Star Wars: Episode I The Phantom Menace, which premiered on May 19, 1999. Nishan shared the screen with her actual twin sister, Nifa Hindes, who played the role of Ann Gella. Their shared scene was shot on B Stage at Leavesden Studios.
Tann's name was not mentioned in the film itself. Her identification first occurred within the established Star Wars canon through the mobile card game known as Star Wars: Force Collection, initially released in 2013. Even though the launch of Force Collection happened before the Star Wars canon's reset in 2014, Leland Chee, a member of the Lucasfilm Story Group, verified that the game was consistently updated to maintain alignment with the canon. The name originally appeared in the Star Wars Legends continuity, specifically in the reference book titled Star Wars: Episode I The Visual Dictionary, authored by David West Reynolds and published on May 26, 1999.