|The First Doctor|
|Portrayed By|| William Hartnell|
Richard Hurndall(in a later episode due to Hartnell's death)
|First Appearance||An Unearthly Child|
|Last Appearance||The Tenth Planet|
|Series||1, 2, 3, 4(first two episodes only)|
|Companion(s)|| Susan Foreman|
|Next Doctor||Second Doctor|
|See Also||The Doctor|
Not much is known about the Doctor's arrival on Earth, what is known, however, is that he was most probably in exile from Time Lords on his home planet of Gallifrey, which he fled stealing a type 40 TARDIS to travel space and through time. The Doctor arrived in London, England in 1963 with his granddaughter, Susan Foreman. On the basis of finding missing parts of the TARDIS, the Doctor and Susan were forced to stay in 1963 England for approximately 5 months. Secretly, however, the Doctor was finding a place to hide the Hand Of Omega. Barbara Wright and Ian Chesterton, two of Susan's schoolteacher's followed her back to the TARDIS one night after noticing her expanded knowledge of Science, even though she couldn't count local currency correctly. Entering the TARDIS, the pair realised its size difference and suspected something alien. Panicking and not knowing how to react, the Doctor kidnapped them and travelled to the year 100,000 BC(also the name of the second episode).
The First Doctor had the stereotypical image of a grandfather; referring to those younger than him as "child" or "my boy", pipe smoking, sharp brown eyes, whiteing hair that ran the length to his shoulders and the use of a walking stick(which doubled as a weapon from time to time). He also wore a blue stoned ring which aided him with certain abilities. The First Doctor, however, was known for adjusting his clothing every time he travelled to Earth's past, he would generally change an item or two to fit in. During The Reign Of Terror, he traded his whole set of clothing for those that a typical French person was wearing. Typically, the First Doctor was youthful and inexperienced as a Time Lord. Unlike future Doctor's, the First Doctor was willing to kill people sometimes, whether it was to save himself or just to speed things up. The First Doctor had little to no respect for Humans, calling them primitive and even electrocuting Ian Chesterton at one point. However, as time progressed, the ruthless, arrogant attitude seemed to develop into a helping, caring person. The First Doctor was an extremely intelligent one and was complimented on this by The Master. However, his intellect could not aid him evade every situation, leaving his companions to save him many times.
 Main Occurences
After arriving in 1963 London with granddaughter, Susan, the Doctor abducted two schoolteachers and travels to the year 100,000 BC. He eventually travels to Skaro, home to the Daleks and explores the Dalek City. When the Daleks eventually attempt an invasion of Earth, the Doctor manages to cease this and later locks Susan out of the TARDIS upon hearing her intentions to marry David(a resistance fighter). Vicki, a human found on Dido, was invited to join the TARDIS crew as she reminded the Doctor of his granddaughter, then took Ian and Barbara back to their homes in 1963. After Vicki's exit, Katarina is made a new companion in the thought that the Doctor was a God. Steven Taylor and the Doctor then argued after the deaths of Katarina and Sara, who were murdered by Daleks. Just before Steven leaves the TARDIS for good, Dodo Chaplet unintentionally joins the Doctor. After fighting off the Cybermen, the Doctor returns to the TARDIS alone, or so he though. Polly Wright and Ben Jackson sneak after him(now that Dodo Chaplet had left) and watch the Doctor, who is plagued by age, regenerate into the Second Doctor.
On occasion Hartnell would fluff his lines in scenes, something that became quite famous in the realm of Doctor Who fans: for example Hartnell once said 'anti-radiation Gloves' instead of 'anti-radiation Drugs' Due to the nature of television filming in the 1960s, where scenes were often done in one continuous take with scenes rarely being re-shot unless something major happened, these mistakes would often make it to the broadcast and they went on to become known as Hartnellisms or Billyfluffs.
Some Hartnellisms were scripted in to the show intentionally, such as The Doctor's constant reference to his companion Ian as Chesterfield despite his name actually being Chesterton, but others have been put down to a medical condition which Hartnell suffered from called arteriosclerosis, a condition that has been linked with memory loss and loss of concentration.
Whether scripted or accidental they became a part of the character of the first Doctor nonetheless