Doctor Who: Doctor Guide

The Doctor who started it all, Hartnell was a strange and mysterious character. Like all the Doctors that followed, he possessed great scientific knowledge, but, unlike most, he hated humans. More often than not, the first Doctor was crass, rude and patronizing to any humans he encountered. He often refused to help those who were in trouble, claiming that it was not his problem. In fact, the only person whom the first Doctor adored was his granddaughter, Susan.

Susan represented the Doctor's “humane” side and often coaxed her grandfather into helping out despite his protests and reluctance. Over time, his attitude slowly began to change, as he bonded with his time-traveling companions and began to enjoy his adventures a bit more. It was also during this Doctor's tenure that the show's most enduring and iconic adversaries, the Daleks and the Cybermen, were introduced. These mighty foes would go on to fight the Doctor's every incarnation in an attempt to “exterminate” him or “delete” him from existence.

When both the first Doctor and the actor portraying him grew weary with age, the time came for regeneration. The Doctor collapsed and morphed into his second incarnation. Initially, neither his companions nor the show's writers knew how to treat him. They started out referring to Hartnell's Doctor in the third-person, but soon settled on the “reincarnation” idea.

This new Doctor's personality was far different from his predecessor. He was disorganized and childish, often referred to by both companions and the show's fans as the “cosmic hobo.” He stored useless rubbish in the pockets of his over-sized coat, wore a ridiculous stove-pipe hat and played the recorder on a whim. Such ridiculous behavior wasn't always unintentional. Somewhere beneath his shabby exterior, lurked the heart of a cold, calculating manipulator. The Doctor often used appearance to make others underestimate his true capabilities, and sometimes even manipulate his own friends into doing his bidding.

The second Doctor's time soon came to a close as well. The lovable space hobo regenerated and became a dapper and suave character with a love for technology and fast cars. Jon Pertwee, just like the two actors before him, took the Doctor and made him his own. Most of the third Doctor's tenure was spent in forced exile on planet Earth, where he agreed – with a great deal of reluctance – to become a scientific adviser for a worldwide organization called UNIT, an endeavor by the United Nations to identify and combat alien threats on Earth.

The third Doctor enjoyed looking good, and always sported expensive smoking jackets and elegant frilled shirts. He often drove around in a futuristic vehicle referred-to by the fans as the “Whomobile.” In general, Pertwee's Doctor was quicker and more physical than the other two. He often physically engaged his enemies head on and was a practitioner of “Venusian Aikido.” He cared deeply for his companions, and even formed a grudging friendship with UNIT's leader, Brigadier Sir Alistair Gordon Lethbridge-Stewart, or “the Brigadier” for short.

In a set of spoilers that will not be revealed here, the third Doctor was badly injured. He made it back to UNIT headquarters and collapsed, only to quickly regenerate into his next form. Tom Baker wasn't nearly as interested in helping improve UNIT and keeping the Earth safe as his predecessor had been. He was a rover and, once fully regenerated, wanted nothing more than to go out exploring and traveling through space and time.

Tired of UNIT and working for the Timelords, Baker's Doctor set off in the TARDIS on his own series of adventures. He was accompanied by a young journalist named Sarah Jane Smith. Despite his whimsical appearance, this Doctor was the coldest and most callous of the lot. He often grew dark and brooding, sadistically taunting his enemies and often doing far worse things than necessary to bring their demise. To his friends, the Doctor is substantially different. He often demonstrates genuine compassion and a fatherly protectiveness, especially towards Sarah Jane. His tenure lasted seven years, the longest any single actor has portrayed the Doctor. Both Baker's and his Doctor's personalities were immensely popular with audiences, and it was he that is credited with popularizing the show in the United States.