Each Doctor Who episode has brought a brand new adventure to screens, but the Doctor’s companions haven’t all shared the same experience. The Doctor Who season 14 cast introduced the Doctor’s latest companion, Ruby Sunday. However, Ruby’s journey in the TARDIS shared similarities to those of her predecessors in Doctor Who’s modern era following the show’s reboot in 2005.

The common links between each of the Doctor’s companions have focused on the locations they traveled to, their attitude toward the titular character, and the benefits of boarding the TARDIS. Some of the greatest Doctor Who stories of all time have included crucial character development for these companions, yet contained multiple instances that created a de ja vu effect because another of the Time Lord’s friends had gone through it before. The Doctor’s companions might have had wildly different personalities, but their experiences were strangely familiar.

10

Witnesses The Doctor Get Emotional About The Time Lords & Gallifrey

The Time War Traumatized The Doctor

Doctor Who season 1 established the heartbreaking destruction of Gallifrey and the race of the Time Lords, leaving the Doctor as the last of his kind most of the time. Although Gallifrey has returned and been destroyed again several times since then, there have been several moments where a companion witnessed the Doctor’s reaction to losing his species and home planet. The Doctor gave an inspiring speech about Gallifrey’s picturesque beauty to Martha in “Gridlock,” for example. The Ninth flew off the handle when faced with the Daleks again in the season 1 episode “Dalek,” too.

Like every companion, Rose learned more about the Time Lord at this moment than at any other point in her travels. The pain and trauma that the Doctor carried for years after the Time War in Doctor Who stuck with them throughout their incarnations and allowed for a more vulnerable and fragile side to the character that wasn’t prominent in the classic era of the show. Although Gallifrey’s status changed often throughout the show, the Doctor’s memories of its extinction didn’t.

9

The Doctor’s Companion Visits A Different Version Of Earth

The Humans Always Arrive Somewhere Similar To Home

One common trip that every companion embarked upon in Doctor Who was the visit to some sort of alternate Earth. Both Rose and Martha visited New Earth, for example. However, not every Earth was necessarily a new planet, and sometimes, it would be a changed version of the original. In the Doctor Who season 14 episode “The Devil’s Chord,” the Fifteenth Doctor showed Ruby her home after Maestro removed music from the world, and in the season 4 episode “Turn Left,” Donna had a parallel Earth build itself around her after changing history.

Occasionally, Earth wouldn’t even be on solid ground. It could be argued that the Eleventh Doctor took Amy to another Earth in “The Beast Below,” except humanity had moved onto individual space stations to represent each former country. Because of the heavy focus on human companions, it made sense that the Doctor would take his latest traveling accomplice to somewhere familiar, but naturally, with a Doctor Who twist filled with danger, anticipation, and fun.

8

Disagreeing With One Of The Doctor’s Decisions

The Time Lord Wasn’t Always Right

Without fail, every Doctor Who companion would have at least one moment when they disagreed with a decision made by the Time Lord. Most of the time, it would be an odd occasion in which they argued back with them. For example, Amy was horrified by the Doctor’s decision to kill the Star Whale to keep humanity safe, but luckily, her rebelliousness saved everyone, including the creature. Sometimes, a companion would disagree with the Doctor running away from making a decision and leaving it to someone else, as the Twelfth Doctor did to Clara in “Kill the Moon.”

However, some companions wouldn’t hesitate to argue back against the Doctor at every turn. Donna Noble was the ideal candidate for this role, and she happily called the Doctor out for their choices. Their second adventure in Pompeii ended in a blazing row, for example. Even when she didn’t remember the Doctor, she still found ways of criticizing the Time Lord, like in “The Star Beast,” when she remarked on the tightness of their suit immediately, despite not having seen them in years and believing them to be a total stranger.

7

The Doctor’s Companion Has A Mysterious Secret That Not Even They Know About

Travelers In The TARDIS Don’t Even Know Themselves

Many of the Doctor’s companions have had a secret that the Time Lord and even themselves weren’t aware of. Rose had “Bad Wolf,” there was the “DoctorDonna,” and Amy and Rory weren’t aware of River Song’s identity in Doctor Who – three prime examples of hidden details a companion wasn’t knowledgeable of. Yet, some mysteries have shrouded a companion’s entire past, present, and future. Clara and Ruby, with their enigmatic stories, stood out, and the fact that they were oblivious to their uniqueness heightened the intrigue surrounding them.

Every version of Clara Oswald, the Impossible Girl, sent an endless number of her personalities across time and space, trying to locate the Doctor throughout their long timeline. Doctor Who season 14’s storyline focused on Ruby Sunday’s mother and father and how her parents were connected to her bizarre ability to produce snowfall at random points and the Pantheon. Even companions like Jack had small complications to their story that they had no answer for, such as why he became immortal after the events of “The Parting of the Ways.”

6

A Member Of Team TARDIS Is Confused By The Doctor’s Two Hearts

The Complexities Of Time Lord Biology

One common fact that always confused the Doctor’s companion was that the Time Lord had two hearts. While every incarnation of the Doctor may have looked human, the biology of the Time Lords was greatly different. However, it was always hilarious when they did discover the Doctor’s double heartbeat. Jackie Tyler made a very funny comment after finding this out in “The Christmas Invasion,” asking, “Anything else [the Doctor’s] got two of?” Bill asked in “Smile” whether the Doctor had high blood pressure and if having more than one heart was a necessity, which was brilliant and enjoyable to watch.

Some companions would question the structure of the Time Lord’s body more than others, however. Ryan was stunned to learn that the Thirteenth Doctor had two pulses after his nurse grandmother, Grace, checked it in “The Woman Who Fell to Earth.” Martha, as a doctor-in-training, was keen to understand more. For example, she remembered learning about the Doctor’s hearts in “Smith and Jones” and was able to help resuscitate them in several episodes. Martha was also useful later, identifying that Jenny didn’t have two hearts like her father in “The Doctor’s Daughter.”

5

Asking The Doctor To Change Timelines & History

Fixed Points In Time Cannot Be Rewritten

One of the biggest issues with time travel was the Doctor’s inability to change the course of history, personal or not. However, the Doctor’s companions often struggled with this restriction. The season 1 episode “Father’s Day” proved the dangers of altering timelines and paradoxes when Rose saved Pete Tyler’s life. While she was heartbroken by the fallout of the events, she eventually understood the Doctor’s difficulties. Clara even threatened the Doctor to go back in time and save Danny Pink, and although there was an opportunity to bring him back, it wasn’t done by the Doctor rewriting history.

Some companions understood this burden of the Doctor’s more than others, however. Martha, Bill, and Ruby all asked about the impact of the “butterfly effect” and knew that sci-fi movie rules dictated that time could be changed with just one wrong step. In fact, one of the best Doctor-lite episodes of Doctor Who, “73 Yards,” focused on this very concept. Although the laws of time travel have frequently switched up throughout the show, the Doctor was always clear about fixed points in time and the catastrophic effects of rewriting history.

4

Getting A TARDIS Key & Superpowered Phone

Boarding The TARDIS Comes With Perks

Coming aboard the TARDIS always came with benefits for the Doctor’s companion, and the two primary gifts they received were a key to the iconic time machine and a superpowered phone. Both of these items were crucial to a companion and often saved their lives. For example, when the Doctor first upgraded Martha’s cell in “42,” it allowed her to ring her mother in her own time to get answers to the ship’s security doors. Rose was able to ring Jackie for comfort when faced with Earth’s destruction in “The End of the World,” too.

However, the TARDIS key was used for so much more than unlocking a door. When the Saxon Master took over Earth in the season 3 three-part finale, the Doctor used his, Martha’s, and Jack’s keys to create makeshift perception filters for them. Even after River taught the Doctor that the TARDIS doors could be opened by snapping their fingers, the Time Lord continued to offer out the keys to new travelers, perhaps as a form of nostalgia or as a symbol to welcome them aboard on a permanent basis.

3

The Doctor Promises To Keep Them Safe, Then Doesn’t

The Time Lord Cannot Be Trusted To Keep Their Companions Out Of Danger

Despite the Doctor’s best intentions, they weren’t always able to keep their companion safe, even though they promised. Whether it was said directly or implied otherwise, the Doctor always swore to keep their friends out of danger and get them back home, but their words weren’t always as strong as their execution. This was demonstrated multiple times throughout the show. For example, the Doctor ensured Jackie knew that they’d get her and Rose out of the Torchwood tower in “Doomsday,” but by the end of the episode, the two were stuck in a parallel world.

The Doctor promised Rory that they would rescue Amy from the Silence in “Day of the Moon,” and although they did, she returned to the TARDIS as “flesh,” not her actual self. Realistically, the only companion the Doctor kept safe was Jack Harkness, who was immortal. But in theory, the Doctor didn’t look after Jack because they didn’t stop Rose from bringing him back. Sadly, the Doctor lost several friends because he pledged to keep them safe, but their hectic adventures throughout time and space were often too extreme to withstand serious harm or even death.

2

The Doctor’s Companion Realizes The Time Lord Isn’t That Impressive

Each Incarnation Of Doctor Who’s Titular Character Have Their Flaws

While the Doctor was always a fascinating figure to their companions, especially because they were alien and had a unique personality, there eventually came a time when they started to see the Time Lord for who they really were. The Doctor was impressive, granted, but not as amazing as their companion thought they were. Donna Noble was a unique companion, however, because she was always unfazed by the Doctor’s knowledge and skills, but that was what made their friendship so special. River was another who didn’t allow the Doctor to show off, but she offered appreciation when it was deserved.

Some companions caught on later than others. When Martha was forced to hide herself and the Doctor in 1913 from the Family of Blood, she realized that the Time Lord had weaknesses and they’d be dead without her support. Rory’s respect for the Doctor slowly grew in Doctor Who, but his first official adventure with the Time Lord, “Vampires in Venice,” showed him that the Doctor wasn’t as glorious as Amy’s childhood stories painted them to be. Although a lot of the Doctor’s character was attributed to their high status and heroic tales, their companions kept them grounded and real.

1

“It’s Bigger On The Inside!”

Gallifreyan Technology Is Hard To Comprehend

Doctor Who’s most iconic quote, “It’s bigger on the inside!” was a common reaction to the TARDIS. The Doctor reveled in this comment and even took the opportunity to repeat it themself in the episode “The Husbands of River Song.” Every time the Doctor introduced a new companion to his ship, their latest friend was always shocked at the Time Lords’ technology, which squeezed a whole new dimension inside a small blue police box. Sometimes, a companion viewed the inside before the out, like Donna in “The Runaway Bride.”

The Doctor was so used to hearing this that they predicted the question or spoke in unison with their companion with great ease.

Interestingly, very few haven’t made the query. A great example of this was Clara’s first scene in the TARDIS in “The Snowmen,” when she instead commented, “It’s smaller on the outside.” This confused the Doctor, who acknowledged it was the first time someone had questioned his ship differently from others. Although the companions always left the TARDIS knowing how to tackle the wider universe, their Doctor Who journey always began with confusion over the ship’s massive interior.