When the Ninth Doctor first met Rose Tyler, she was a very emotional nineteen-year-old living on a London council estate who left school with minimal educational achievements. Shaped by living with her promiscuous mother and stories about her father she never knew, Rose was destined for a life in retail. However, the Doctor blew up her store and the pair began travelling together afterwards. Rose helped the Doctor work through some of the pain he harbored from surviving the Last Great Time War. When she met the Doctor, Rose was the girlfriend of Mickey Smith, but their relationship began to decay after she started travelling in the TARDIS. As Mickey himself noted, she transferred her romantic attention to the Doctor.
A major facet of her time in the TARDIS was that she had caused a temporal paradox by which she was the reason she became the “Bad Wolf”. Leaving clues throughout history that she was able to recognise when all her hope had evaporated, that helped find her way back to the Doctor, even though he had abandoned her and the TARDIS. Unable to actually fly the time machine, she stared into its heart, which enfolded her in time vortex energy and turned her into a new and seemingly omnipotent being capable of rescuing the Doctor. The experience nearly killed her and forced the Doctor to absorb the time vortex energy and transfer it back to the TARDIS — a traumatic act that naturally triggers regeneration.
Rose was forced to stop travelling with the Tenth Doctor once she was pulled into a parallel universe. She spent years trying to find a way back to the Doctor and when she found one, the Doctor explained that she had to remain in her new universe with her mother, new baby brother, that universe’s Pete Tyler and, for a time, Mickey. Ultimately she got most of her wishes fulfilled when a duplicate Tenth Doctor came to live out the rest of her life with her.
Mickey Smith was an auto mechanic and resident of the Powell Estate who came to befriend the Doctor, Sarah Jane Smith, Captain Jack Harkness, Jackie Tyler and another universes’s Peter Tyler by virtue of his former romantic relationship with Rose Tyler. A typical teenager, he rose to become a principal defender of not just one, but two planets Earth. After years of living with the Tyler family on the parallel Earth, he returned to his “home Earth” and married Martha Jones. Despite close ties to the Torchwood Institutes of two Earths, he and his wife ultimately struck out on their own to become “freelance” alien fighters.
Sarah Jane Smith
Sarah Jane Smith was an investigative journalist who travelled with the Doctor in histhird and fourth incarnations. She reunited with him in histenth incarnation and had adventures with him and hisimmediate successor. Sarah Jane met nine of the Doctor’s incarnations in total: those already mentioned and the First,Second, Fifth, Sixth, and Seventh. Due to her experiences with the Doctor, she was entrusted with the task of protecting Earthfrom hostile extraterrestrials and helping peaceful aliens. She shared these adventures with her young companions/surrogate family.
After many trips with her, the Fourth Doctor received a summons to return to Gallifrey, his home world. He told her then that they had to part company because humans weren’t allowed on the planet. Their final words to each other were pleas to not forget them. Standing in the street, watching the TARDIS dematerialise, Sarah realised that, in attempting to take her home, the Doctor had not only missed landing on Hill View Road, but had not landed in South Croydon at all. She remarked to a nearby dog, “He blew it,” before walking off toward her new life. Indeed, the Doctor had mistakenly left her in Aberdeen, Scotland.
Jacqueline “Jackie” Tyler was a resident of early 21st century London and the mother of Rose Tyler. She lived with Rose in a council flat on the Powell Estate as a single mother. Jackie was one of the first people to encounter the Doctor after he regenerated into his tenth incarnation. Like Rose, it took Jackie a while to realise this younger-looking man was the same one she had met before. Her relationship with the Doctor was warmer than his earlier incarnation; she allowed the Doctor to attend Christmas dinner with Rose and her.
Following the defeat of Davros, the Doctor returned Jackie to the alternate Earth to reunite her with her husband and son. Jackie couldn’t resist winding up the Doctor one last time by making him believe she had named her son “Doctor”. She watched as the Doctor’s clone agreed to stay behind and begin a life with Rose and the original Doctor departed for the last time.
Donna Noble, later known by some as “Doctor Donna”, was a companion to the Tenth Doctor. Despite her ordinary origins, she was described by both Rose Tyler and the Tenth Doctor as being the most important woman in all of creation, due to her saving the whole of reality from the Daleks and Davros. To survive the side effects of her transformation into the “Doctor Donna”, her memories of her time with the Doctor were forcibly erased and she was returned to Earth. She later married Shaun Temple, and became Donna Temple-Noble.
After a brief encounter with the Doctor during her wedding in 2007, Donna and the Doctor crossed paths again in 2009 while investigating Adipose Industries. After Donna stopped the birthing of the Adipose from fatally converting human tissue into Adipose young, she witnessed the March of the Adipose and began travelling in the TARDIS. Unlike many companions, she was well prepared for the trip having packed several suitcases. After assisting the Doctor in exiling the Meta-Crisis Doctor to Pete Tyler’s World and saying farewell to Rose, Donna’s mind overloaded, a consequence of the unbearable Time Lord-human meta-crisis. To save her life, the Doctor was forced to erase the memories of all their adventures.
Dr. Martha Jones was a physician. She met the Tenth Doctor during her residency at Royal Hope Hospital in London when the hospital was transported to the Moon by the Judoon, after which she began travelling with the Doctor.
Unlike other companions, she not only fell in love with the Doctor but also declared her feelings. She decided to stop travelling with him when he failed to return her affection, but continued to have a number of adventures both with and without him, due to her work with UNIT and Torchwood.
Captain Jack Harkness
“Captain Jack Harkness” was the alias adopted by a Time Agent and con man from the 51st century who became an associate and occasional companion of the Doctor. After being exterminated by a Dalek, he was revived by Rose Tyler after she absorbed the Time Vortex. Unable to control her powers, Rose accidentally turned him into an immortal being. Because of this, the Ninth Doctor saw Jack as a fixed point — a temporal paradox that threatened the TARDIS’ proper operation. Consequently, the Doctor abandoned him in the year 200,100 aboard a space station orbiting a Dalek-devastated Earth. Stranded, Jack had to use his own devices to catch up to the Doctor. He thought it likely that he’d find the Ninth Doctor in the early 21st century, since that was Rose’s home era. But his vortex manipulator failed to deliver him there, leaving the immortal no choice but to simply wait from the mid-19th to the early 21st century to reconnect with the Doctor.
During his long wait for the Doctor, he experienced Earth’s history first hand. For the majority of those years, he also worked for Torchwood Three. For several decades an informal free-lancer, he eventually became its head in the year 2000. Later that decade, he finally met up with the Doctor, although the Time Lord had by this time regenerated into his tenth form and was now travelling with Martha Jones.