Tamsin Drew

Tamsin Drew was a companion of the Eighth Doctor, until she was turned against him by the Meddling Monk and became his companion.

Meeting the Doctor
Tamsin came from Dulwich and was an actress. Before she met the Doctor, her career was going badly due to her age. She answered an advertisement which read:

Traveller in Time and Space seeks male or female companion with good sense of humour for adventures in the Fourth and Fifth Dimensions No Experience Necessary. No time wasters, no space wasters, please.

She answered under the alias of Juliet Walsh, a strong, career-driven woman, and found herself auditioning, with Theo Lawson, Asha Qureshi and Hugh Bainbridge for the role of the Doctor's new companion. "Juliet" was the first of the possible companions to be eliminated and Tamsin went home upset.

She had taken the jacket of a scientist who controlled many robots and was attacked by one. The Doctor stepped in and saved her.

Asha, Theo and Hugh were all found to have malicious reasons for wanting to join the Doctor. After they were sorted out, "Juliet" revealed herself to the Doctor as Tamsin Drew and he decided to take her with him. (AUDIO: Situation Vacant)

Adventures and the Monk
The Doctor and Tamsin's first adventure was on the devastated world of Corinth Minor. They met war criminal Morella Wendigo. (AUDIO: Nevermore) After sorting matters there, they arrived at Kells Abbey in 1006. The Doctor was surprised to meet an old foe, the Monk, who was trying to steal the Book of Kells. (AUDIO: The Book of Kells)

Leaving the Doctor
The Doctor and Tamsin arrived on Deimos Moonbase, which had become a museum containing Ice Warrior artefacts and the atmospheric re-ioniser that was part of a failed terraforming project to create a breathable atmosphere on Mars for humans. A group of nine Ice Warriors led by Lord Slaadek — noted by one of them as "the last of our race", though as the Doctor pointed out to him, "there [were] some more of you frozen out in the asteroid belt" — (AUDIO: Deimos) had been awakened prematurely by the Monk to change the course of history. (AUDIO: The Resurrection of Mars)

While the Doctor went out to negotiate with the Ice Warriors, Tamsin stayed behind to make sure that the base's supervisor, Temperance Finch didn't use the base's microwave emitters to kill the Ice Warriors and their hostages. However, Professor Boston Schooner had already sabotaged the controls. As Tamsin had basically confessed to Gregson Grenville that she intended to sabotage them herself, she was imprisoned. The Doctor and Gregson, realising their mistake, freed Tamsin. Tamsin helped Gregson plant mining explosives to stop the Ice Warriors.

The Doctor and Tamsin boarded the rocket, but Gregson failed to make it. The rocket took off, killing Gregson and two Ice Warriors. Knowing the sabotage would eventually be reversed, the Doctor was about to use the remote device to detonate the explosives, but had received a "text message" from Lucie, (AUDIO: Deimos) whom the Monk had placed on the base as part of his plans.

After falling out with the Doctor for wanting to save Lucie, but seemingly not caring about Gregson, Tamsin met the Monk, who took her in his TARDIS to show what the Doctor's interference would have caused. The Monk took Tamsin to the aftermath of the Ice Warriors' attack on Halcyon around the 33rd century, convincing her that the Doctor was responsible for the billions of deaths there, and subsequently showing him apparently collaborating with the Ice Warriors in killing 600 people on a passenger rocket.

Returning to the base, Tamsin met Lucie, who had been turning up the ambient temperature to slow down the Ice Warriors so that the Doctor could meddle with the re-ioniser and correct what the Monk was doing, preventing the deaths of the thousands of human colonists on Mars.

When Lord Slaadek threatened the life of the Doctor, Lucie agreed to decrease the temperature again so that the Doctor would live. The Doctor, unable to reverse the effects, brought the re-ioniser "to a very sudden halt with a very loud bang" by reducing a critical feedback in the ionisation beam, giving everyone about five minutes to escape. At the last minute, the Doctor also made the process alter Mars into an Earth-like atmosphere rather than that of the Mars of long before.

Tamsin told the Doctor she had "had enough" of what she considered only looking out for his friends and the Web of Time, and condemning the fate of Halcyon in the future to the Ice Warriors and left with the Monk. The duo set off to find "some old friends who also [had] a score to settle with the Doctor" to "combine their talents". (AUDIO: The Resurrection of Mars)

Tamsin helped the Monk collect human artefacts on Earth while the planet was being invaded by the Daleks. (AUDIO: Lucie Miller) After Tamsin learned of the Monk's involvement in the invasion, she helped the Doctor try to stop the Daleks. Shortly after, the Daleks surrounded her, the Monk, and the Doctor. While the Monk was spared for aligning with the Daleks and the Doctor was considered a valuable prisoner, the Daleks disregarded Tamsin as "surplus", and immediately killed her. The Monk mourned Tamsin's death, as he had developed strong feelings for her. Seeing this, the Doctor berated the Monk for allowing her to be the first of billions to die because of his actions in aiding the Daleks, and for not realising what he had done had guaranteed her eventual murder. (AUDIO: To the Death)

Later references
When the Eighth Doctor was about to regenerate he remembered Tamsin among his past companions. (TV: The Night of the Doctor)