Doctor Who may be best known for the Time Lord at its heart, but the show is made up just as much by the Doctor’s companions. Series 11 is fast approaching and Whovians all around the world are busily speculating as to what the upcoming season may hold. One of the key points of curiosity is the identities and personalities of the Doctor’s new companions, Ryan, Yasmin and Graham.

Within the show’s universe, the companions give the Doctor someone who can help stave off the soul-crushing ennui that comes from being an outcast or (in the revival series) the last surviving member of the Time Lords. It’s also smart not to travel alone, particularly when you have a time-traveling spaceship, and the companions frequently have skills and talents which the Doctor lacks to help to save the day. Within the context of the show’s writing, the companions also give the Doctor someone to whom things can be explained for the benefit of the audience.

Sadly, not all companions are created equal and not everyone who joined the Doctor for the journey of a lifetime was worth the time of The Doctor - or the audience. For every strong, confident person capable of standing by the Doctor’s side in a crisis, there were many who screamed or fainted at the first sign of danger.

What follows is a brief assessment of some of the best and worst of the many characters who traveled on The TARDIS with The Doctor. Some of them set the gold standard for everything a sidekick should be. Others were failed by the writers, who didn’t develop them into companions worthy of the name.

Best: Rose Tyler

A 19-year old shopgirl who first encountered the Ninth Doctor after he blew up the department store where she worked, Rose Tyler was the first companion following the revival of Doctor Who in 2005. Played by then-pop-star Billie Piper, some Whovians criticized Rose’s character for becoming love-struck by the dashing Doctor and for being selfish, having abandoned her boyfriend and her mother to travel the galaxy.

Despite this, many felt that Rose offered an all-too-human perspective on the Doctor’s adventures. For better or worse, her journey from shopgirl to Defender of the Earth struck a chord with many people who were introduced to the show through her eyes. She also summed up what makes the Doctor so special for so many fans: he shows you “a better way of living your life.”

Worst: Kamelion

Kamelion was a shape-changing robot, whom the Fifth Doctor rescued from the machinations of the Master. Kamelion traveled with The Doctor for a short time before once again falling under the Master’s control. Regretfully, the Doctor destroyed Kamelion at the android’s urging, before it could be turned upon its friends. Threepio he was not.

The chief problem with Kamelion was that his character was built around a real robot producer John Nathan-Turner had purchased for the show. The shape-shifting gimmick was added after it became apparent how prone to malfunction the robot was, and that was before the only engineer who knew how to program Kamelion passed-on after a boating accident! Kamelion was written out of the show and Fifth Doctor actor Peter Davison said that any sadness he showed at the robot’s passing on-camera was “pure acting.”

Best: Leela

A huntress of the Sevateem, Leela was cast out of her tribe for blasphemy. (i.e. asking too many questions). Clearly intelligent despite her savage upbringing, Leela quickly endeared herself to the Fourth Doctor, who tried his best to educate her in the ways of space-faring civilizations. The two represented a unique balance, with the pacifist Doctor trying to talk his way out of trouble Leela thought it best to confront with a sharp knife’s edge.

While the Doctor had soldier and warrior companions before, Leela was a first for the series, being a woman who was a more capable fighter than the Doctor and not adverse to physical confrontations. No other companion has quite managed to live up to Leela’s example in that department and she inspired the equally hot-tempered warrior woman character of Turanga Leela from Futurama.

Worst: Martha Jones

When Billie Piper left Doctor Who, it was felt the next companion should be an equal partner to the Doctor. Enter Martha Jones - a well-off medical student who was a far cry from working-class Rose Tyler. That was the theory, anyway. The reality was that Martha soon developed an unrequited crush on the Doctor and whined to anyone who would listen about his failure to notice her.

What truly made Martha awful was her failure to learn anything from her time with the Doctor. She left him to join UNIT - a military organization formed to fight alien invaders. She became part of an effort to blow up the Earth rather than let the Daleks take it in the episode “Journeys End” - an action the Doctor later condemned her for, in the story “Don’t Step On The Grass.”

Best: K9

Created by Professor Marius, a dog-loving scientist who was unable to take his pet pooch with him after being assigned to a lab in deep space, K9 was both a loyal companion and a state-of-the-art analytical machine. The Fourth Doctor later adopted K9 at Marius’ request and would go on to build several versions of him as guard dogs for his most beloved companions, after they had parted ways with him.

K9 is one of the most beloved of the Doctor’s companions. In addition to being one of the few companions to merit his own spin-off television series, K9 And Company, K9 is the only one to merit their own movie. Granted, the movie is set outside of the standard continuity of Doctor Who, but it’s still an impressive feat.

Page 2 of 2: More Of The Best And Worst Doctor Who Companions

Worst: Adric

A native of the parallel universe called E-Space, Adric’s proudest accomplishment in his young life was earning Elite status for his mathematical knowledge. This designation would have marked him for higher education, had he not stowed-away on-board The TARDIS.

Legend has it that Adric was created for Doctor Who for the same reason Robin was created for Batman - to give the typical fan a point-of-view character they could relate to. Given that Adric was a disagreeable math nerd, this may say quite a bit about how the writers of Doctor Who at the time viewed their audience. It didn’t help matters that actor Matthew Waterhouse, who played Adric, was incapable of holding his own alongside an actor with the gravitas of Tom Baker. Few were sad when Adric perished trying to stop a space-freighter from crashing into prehistoric Earth.

Best: Rory Williams

Most men would start reconsidering their wedding plans if their fiancee started talking about how her imaginary friend from when she was a girl was real and had visited her the night before their wedding. Luckily for Amy Pond, Rory Williams is not most men. A registered nurse before he became the intergalactic legend known as The Last Centurion, Rory’s time with The Doctor would see him perish several times trying to save the love of his life and the universe. Death and erasure from reality only slowed him down.

Perhaps the best summation of Rory Williams’ character and why he is so beloved comes from one of the many Chuck Norris inspired memes regarding his exploits. “That which does not kill Rory Williams only makes him stronger. In addition, that which does kill Rory Williams also makes him stronger.”

Worst: Perpugilliam “Peri” Brown

An American botany major who first encountered the Doctor in the episode “Planet Of Fire,” Peri Brown made a strong impression in her first appearance. Confronted by The Master, who attempted to hypnotize her by shouting “I am the Master!” Peri responded “So what? I’m Perpugilliam Brown, and I can shout just as loud as you can!” Unfortunately, Peri would show little of this wit in later episodes.

Another victim of the lackluster writing that plagued the Sixth Doctor era of Doctor Who, Peri went from a spirited young woman to a shrill, nagging presence who didn’t seem to enjoy traveling with the Doctor at all. Thankfully, actress Nicola Bryant and Sixth Doctor actor Colin Baker would later get a chance to play more dignified versions of their respective characters in the short-film series The Stranger.

Best: Sarah Jane Smith

First appearing in “The Time Warrior”, reporter Sarah Jane Smith was quick to establish herself as a different sort of companion. An outspoken feminist with little respect for rules or convention, the only person who could match Sarah Jane in sheer nerve might be Lois Lane. She would go on to become one of The Doctor’s longest-serving companions.

When Doctor Who was revived in 2005, there was no question who would be the first companion from the classic series to return for a cameo once the show was reestablished. Sarah Jane Smith joined forces with The Doctor once again in the second series episode “School Reunion.” The episode proved that Sarah Jane was as popular as ever, leading to a solo spin-off, The Sarah Jane Adventures, which ran until the untimely passing of actress Elisabeth Sladen in 2011.

Worst: Adam Mitchell

Adam Mitchell holds a special place among The Doctor’s companions, having the dishonor of being the only person to be kicked out of the TARDIS. While many of the Doctor’s companions have been cowardly, greedy or deceitful, none of them ever sank to the depths that Mitchell did.

Taken to the future on his first trip in the TARDIS, Mitchell acquired a technopathic implant and attempted to send information about future technologies to himself in the past, in a bid to become rich. This effort almost got the Doctor and Rose Tyler killed, when information about them was sent from Adam’s mind through the network to an alien intelligence that almost took over the TARDIS. Had Adam been apologetic, it might have made a difference. Instead, he blamed The Doctor for his mistakes, before pathetically begging for a second chance.

Next: Doctor Who Season 11: Every Update You Need To Know