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."
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."
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."
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.