With Jodie Whittaker on her way out as the Doctor and her final episode of Doctor Who taking place during the centenary celebration of the BBC, her final episode is sure to be spectacular. While fans don't yet know who will be replacing her, it is known that some familiar faces will be returning for the Thirteenth Doctor's swan song.

At the end of the Easter special Legend of The Sea Devils, the teaser for the finale revealed two returning former companions: Ace, played by Sophie Aldred; and Tegan, played by Janet Fielding. Previously, we've looked at the history of Ace and her role in the show. Now, it's time to find out more about Tegan Jovanka before she makes her return later this year.

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Tegan Jovanka was a companion to both the Fourth (Tom Baker) and Fifth (Peter Davison) Doctors, although her involvement with the Fourth Doctor began as he neared his regeneration. Making her debut in 1981, Tegan happened upon the TARDIS while she was on her way to her first day as an air stewardess. Her Aunt Vanessa was driving her when the car broke down on the way, leading Tegan to wander into the TARDIS without the Doctor or Adric noticing, meaning they took off with her aboard.

They land on Logopolis where, after stumbling through the expansive ship's interior, Tegan finally comes across the console room and meets the Doctor and Adric. Unbeknownst to Tegan, while she was looking for help to fix the broken down car, The Master had murdered her aunt Vanessa. Once the Doctor explains the situation to her, Tegan agrees to help him and Adric take down The Master.

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Tegan herself originally came from Australia and grew up on various cattle farms, but after her father had an affair, she moved to the coast with her mother. Eventually, she was sent to boarding school; however, that didn't last long before she was expelled. After her expulsion, she was sent to live with her aunt Vanessa in London. It was here that she pursued her love of airplanes and became an air stewardess. However, due to her unexpected run-in with the Doctor, that job was put on hold.

At the end of her first adventure with the Fourth Doctor, he was mortally wounded, leading to his regeneration. During her adventures with the Fifth Doctor, Tegan continued to try to return to Heathrow and her normal life. However, every time The Doctor tried to return her, they ended up on a new adventure that was decidedly not in Heathrow.

During their adventures, headstrong and stubborn Tegan was more than a match for the Doctor. Self-described as "a mouth on legs," Tegan was direct, blunt, and loud, never afraid to speak her mind even if it directly went against the Doctor's opinions or wishes. They butted heads, but worked well together, and Tegan became friends with other companions Adric and Nyssa. At the end of season 19, they finally landed at Heathrow and once again defeated The Master, after which the Doctor and Nyssa left Tegan behind. However, in the very next season, Tegan ended up rejoining Team TARDIS after Omega kidnapped her cousin to lure her to him. From here, Tegan voluntarily joined the Doctor on his adventures, including taking part in the "Five Doctors," episode where the five incarnations of the Doctor thus far all appeared together.

While on their travels, the Doctor often bolstered Tegan with the words "Brave heart, Tegan;" however, she would frequently tell him not to say it. He disregarded her wishes and said it anyway, and despite her protestations, she said the phrase to Nyssa and also whispered it to herself as the TARDIS left her at Heathrow.

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It came time for Tegan to leave The Doctor after they encountered the Daleks in the episode "Resurrection of The Daleks." The TARDIS is dragged through a time corridor back to Heathrow in 1984, where Tegan is captured by Daleks but ultimately helps to defeat them. However, the horrors of the Dalek Civil War led to Tegan deciding to leave the Doctor, as traveling had stopped being fun.

Much like Ace, Tegan also continued to have adventures in the expanded media universe for the show, appearing in comics, books, and audio plays. Once back on Earth, Tegan also worked tirelessly for Aboriginal rights and married Dr. William Haybourne, a lecturer at Exeter University. At some point, Tegan also spoke with River Song and was interviewed by UNIT before having her memories erased.

What role could Tegan be playing in Thirteen's finale? It's hard to say for sure, but from what has been teased so far, it's clear that she teams up with Ace after not seeing the Doctor for nearly four decades. The footage revealed so far sees both women taking up arms against an unknown enemy, although it could be the Cybermen judging by the rest of the trailer. It also seems as though any of her adventures in the extended media may be retconned. Regardless, both Tegan and Ace have long been beloved companions, and having these two strong women team up together can only lead to something epic.

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