Tania Bell

Tania Bell was a companion of the Eighth Doctor, member of Torchwood Three and a resident of 107 Baker Street in 2020.

Early life
Tania was transgender, a fact that some people did not like. (AUDIO: Wild Animals) As a child, her father often told her to leave the house for upsetting her mother. (AUDIO: Lost Property) She was not often treated as Andy Davidson felt that she should have been. (AUDIO: Snow)

By 2014, Tania was part of Torchwood, (AUDIO: Lost Property) receiving basic martial arts training (AUDIO: Snow) and moving into Flat 1 at 107 Baker Street (AUDIO: Lost Property) to keep an eye out for the Doctor, who was known to visit the address from time to time. She was in contact with Sergeant Andy Davidson and, unbeknownst to her, had her flat bugged with cameras. (AUDIO: Must-See TV)

The Doctor's arrival
In 2020, Tania finally met the Doctor in his eighth incarnation when he moved in with Helen Sinclair and Liv Chenka, to whom she was attracted. (AUDIO: Lost Property) She was aware that it was too early in his timeline for him to know about Torchwood and, thus, had to keep him from finding out about her affiliation. (AUDIO: Must-See TV)

Tania suggested that something might be exacerbating tensions in the house when arguments and paranoia abounded. Once the Doctor had put a stop to it, she made a telephone call and told Torchwood that the Level 2 activity had been resolved with no further action being necessary. (AUDIO: Lost Property)

Although Liv refused due to a prior experience, Tania offered both Liv and Helen smart phones. Helen asked her to visit Liv in the hospital after she was shot and fell unconscious. Tania asked Liv out for dinner after she woke up and told her that she was transgender, which Liv was unfazed by. (AUDIO: Wild Animals)

Andy visited the house after Tania went somewhat quiet, annoying Tania as the appearance of a police officer made Liv suspicious. She was further irritated to find that Torchwood had bugged her flat and smuggled Andy in to point them out so that she could remove them. She and Liv later agreed to a "no questions, no lies" policy with regards to their secrets. (AUDIO: Must-See TV)

As Torchwood needed the Doctor to not be a "broken man", Tania directed him towards Mr Crusoe, which angered Andy. Her date with Liv was hijacked by the Doctor and attacked by Teeja and Bourakai, whom Tania helped chase. Following their defeat, Liv took Tania and Robin Bright-Thompson to a pub to tell them who she really was. (AUDIO: Divine Intervention)

After the pub, the Doctor invited Tania to join him, Liv and Helen on a test flight in the TARDIS. They were joined by Andy and ended up 6 million years in Earth’s future. The Doctor and Tania explored the ruins of London together, with him telling her about regeneration. Liv and Andy led a decontamination sentinel to them, which the Doctor told them to disable with rocks. Realising an army of the robots was approaching, he gave Tania a TARDIS key and told her, Andy and Helen to return to the TARDIS. The ship refused to let them in, so Andy took the opportunity of them being trapped to confess that Torchwood had actually been shut down. When the Doctor, Liv and Robin returned the TARDIS yielded and the Doctor took them back to 2020. (AUDIO: Dead Time)

Tania insisted on joining the Doctor in going back in time to 1941 to investigate an unexploded bomb which had just been unearthed in 2020. Liv followed her to the bomb site, discovering an alien stasis pod, and together they stopped the stasis spreading beyond the site. Emerging after days in and out of stasis, they reunited with the others and returned to 2020. (AUDIO: Baker Street Irregulars)

Tania travelled with the Doctor to 2050 to investigate the altered future, along with Liv, Helen and Andy. They were all immediately captured by forces opposing Divine Intervention and Tania was subsequently interrogated by Gemma Houlbrooke. The Doctor eventually convinced Gemma to release them and they returned to 2020. (AUDIO: The Long Way Round)

Repairing the timeline
Using the Paradoxica, the Doctor placed Tania and Helen into a vision of the planet Flask where they were constantly confused as to where they were and what they were doing there, whilst hiding from a squad of Judoon sent after them by Mr Bird. Once back in the TARDIS, Helen realised that the Doctor paired her and Tania up so as to not give away hints of a future child she and Liv might share. (AUDIO: Patience)

On Rarkelia, Tania assisted the Doctor in putting a stop of Divine Interventions rule over the planet by suppressing the population's natural song, capable of destroying a local parasite that had begun preying on the populus. Tania was thoroughly distressed when she saw Liv on a broadcast suffering from a deliberate injestion of the viral strain by Professor Victoria Wilks; however, the Doctor's intervention was able to destroy the parasite, thus saving Liv's life. (AUDIO: Twisted Folklore)

Back in 2020, Tania and Liv got into an arguement over their future when the TARDIS was fully restored. Liv accompanied the Doctor to 2035 where she and Andy got separated from them by attacks and came across a future version of Tania, who got killed in an incursion. In a fit of grief, Liv determined to stay but the Doctor told her that the Tania she met was the product of a potential future that may not come to pass. Returning to 2020, Liv was relieved to see Tania alive and well. (AUDIO: Snow)

Tania didn't accompany the others in looking for the leader of Divine Intervention but greeted them when they return, only to be informed that Andy was lost in the process. (AUDIO: What Just Happened?)

When the Doctor goes to catch Robin when he left Baker Street and Helen accompanied them, Tania started suffering from temporal occlusion as a result of Helen interacting with her a few months prior. While the past Tania and Helen followed the Doctor onto Robin's train and wound up persued by the Void and Mr Bird, the present Tania was brought to the Curator by Liv and her memories were stablished by one of his pictures. After the Curator brought the two Tanias into the same time zone, their coming into contact resolved the immediate danger (AUDIO: Crossed Lines). The stress rendered Tania exhausted and she retired for some rest while the Doctor attempted to rescue Andy. (AUDIO: Get Andy)

When the group get trapped in 107 Baker Street as it's eaten away by the paradox, Tania discovers that she, Andy, Liv, Helen, the Doctor and Robin all possessed the original keys to the house, which possessed unique temporal properties. Tania used her key, along with Liv, Helen and Andy, to retrieve the Doctor and Robin from the collapsing attic of 107 when the timeline was finally restored to the original 2020, where they discovered the world is stuck in a global lockdown. (AUDIO: The Keys of Baker Street)

With the TARDIS still grounded until the end of the year, Tania partook of the lockdown with Liv, commending her efforts as an essential worker on account of her medical background. Towards the end of the year, Liv, still undecided on her future, tried to convince Tania to accompany her in the TARDIS but Tania insisted that she was rooted and couldn't leave Earth while it was in such a bad state. While Liv did initially leave in the TARDIS, she returned moments later and announced that she was there to stay for good, to Tania's jubilation. (AUDIO: Best Year Ever)

Personality
Tania described herself as nosy (AUDIO: Lost Property) and told the Doctor that she enjoyed shopping whenever she was upset. (AUDIO: Divine Intervention)

Behind the scenes
Tania is the first transgender companion in any Doctor Who media.