Vislor Turlough (Mark Strickson) was a student from the planet Trion, who was placed with the Fifth Doctor by the evil Black Guardian, for the purpose of executing a nefarious agenda. This led to a particularly fraught interpersonal relationship for a Doctor with a broad range of companions. The Fifth Doctor’s last – the American botany student, Peri Brown (Nicola Bryant) – was the character for whom The Doctor sacrificed himself when poisoned.
Ace (Sophie Aldred) was a very popular companion when she appeared alongside the Seventh Doctor. She was a human teenager who had been suddenly transported to the planet Svartos by a freak time storm. When their paths crossed, the Doctor came to realize that a great deal of the trauma Ace experienced in her childhood was the result of the actions of his enemy Fenric, and Ace and the Doctor developed a close bond confronting their mutual Fenric-related issues.
Jack Harkness (John Barrowman) was the second of the Doctor’s companions to launch a successful spinoff series – this time in the form of Torchwood (2006-2011). Harkness first appeared with the Ninth Doctor as a time traveller from the 51st century. By the time he interacts with the Tenth Doctor, he’s immortal and on his way to running the Torchwood organization. His character is also particularly notable for being the first openly bisexual character in the Doctor Who franchise. He appeared in the same era as Rose Tyler (Billie Piper), whose introduction in the first episode of the Doctor Who relaunch in 2005 heralded a new chapter for the use of the companion characters.
Rose is used in this episode as an audience proxy – a move that’s vital to the success of the relaunch overall. By 2005, Doctor Who had been absent from television for almost a decade, and Rose allowed us to meet The Doctor anew, through her eyes. Rather than handing the lead over to The Doctor at that point, though, Rose retained essentially equal status within the story of the show and, as such, was instrumental in determining the direction of the narrative. Though she began the show as a teenage shop assistant from London, she spent her run as Doctor’s companion repeatedly saving the universe. With the Ninth Doctor, she absorbs the energy of the Time Vortex, and with the Tenth Doctor, she helps him combat the Daleks and is sealed in a parallel universe as a result.
Martha Jones (Freema Agyeman) joined the Tenth Doctor on his travels after their paths crossed during an incident at the hospital in which she was studying. Martha proved to be a highly capable companion – as deft with action and adventure as she was with strategy and inter-personal relationships. Though she and The Doctor parted ways eventually, her character did not fall from view entirely. Instead, she cropped up within the realms of the spinoff show Torchwood on occasion – catching up with former fellow companion, Jack Harkness.
River Song (Alex Kingston) is perhaps the companion most integral to the overall story of The Doctor. She first appears with the Tenth Doctor, but soon makes it clear that her story with him is long and complex. At different times, she’s been his companion and his wife, but since they’re both time travellers, their interactions are out of chronology. This means that his first interaction with her, in a 2008 episode, is her last.
Over the course of the following seasons, however, The Doctor learns that River Song is the daughter of the companions accompanying the Eleventh Doctor – Amy Pond (Karen Gillan) and Rory Williams (Arthur Darvill). Since she was conceived by the couple aboard the TARDIS while it travelled through a Time Vortex, she absorbed traits and abilities similar to those of a Time Lord. This means she can regenerate and – though she was kidnapped as an infant – she’s actually been a regular presence in the lives of The Doctor and her parents.
Clara Oswald (Jenna Coleman) has a long and storied connection with The Doctor, too. The Time Lord encountered her as three distinct people in three different eras, and became determined to solve the mystery of her multiple lives. The 21st century version, as appearing with the Eleventh Doctor, is found to be a teacher at Coal Hill School – the location seen in the first ever episode back in 1963, and the series spinoff, Class, in 2016. During her tenure, she persuades the War Doctor to change time – resulting in the survival of Gallifrey and the Time Lords.
