The
First Doctor grew progressively weaker while battling the
Cybermen during the events of
The Tenth Planet (1966) and eventually collapsed, seemingly from old age. His body renewed itself and transformed into the Second Doctor. Initially, the relationship between the Second Doctor and his predecessor was unclear. In his first story, the Second Doctor referred to his predecessor in the
third person as if he were a completely different person. His companions
Ben and Polly are at first unsure how to treat him, though Polly is willing to believe he is the same man, and it is only when a
Dalek recognises the Doctor that Ben accepts that he is the Doctor. This all occurred during the new Doctor's first story,
The Power of the Daleks (1966). In the second story,
The Highlanders (1966–67),
Jamie McCrimmon joined the
TARDIS crew, and remained with the Second Doctor for the rest of his travels. At the conclusion of
The Faceless Ones (1967), Ben and Polly left together when the TARDIS landed at
Gatwick Airport on the same day they originally left with the First Doctor, after they had stopped the mass kidnapping of tourists by shape shifting aliens. In the following story
The Evil of the Daleks (1967), the Doctor and Jamie became involved in a plot by the
Daleks to gain both the "Human and Dalek Factors" when the TARDIS was stolen, which led to them meeting
Victoria Waterfield in the 19th century. The Doctor used the situation to engineer a Dalek civil war that seemingly destroyed the Daleks forever. However, Victoria's father was among the casualties. Now an orphan, Victoria chose to accompany the Doctor and Jamie on their travels. Although she felt great affection for the Doctor and Jamie, she was never able to completely come to terms with life in the TARDIS and the constant danger that resulted. She eventually chose to leave after the events of
Fury from the Deep (1968) and was adopted by Mr. and Mrs. Harris in the 20th Century. After the events of
The Wheel in Space (1968), the Doctor and Jamie were then joined by
Zoe Heriot, an extremely intelligent woman from the 21st century, who helped defeat the
Cybermen attack on a space station known as the Wheel. She then stowed away in the TARDIS and, despite the Doctor's warnings about what she might encounter, chose to remain. During his second incarnation, the Doctor confronted familiar foes such as the
Daleks and the Cybermen, as well as new enemies such as the
Great Intelligence and the
Ice Warriors. It was during
The Web of Fear (1968) that he first met
Colonel Alistair Gordon Lethbridge-Stewart, in the tunnels of the London Underground. Following the defeat of the Great Intelligence, Lethbridge-Stewart was promoted to Brigadier and became the leader of the British contingent of
UNIT, a military organisation tasked to investigate and defend the world from
extraterrestrial threats. In
The Invasion (1968), the Doctor reteamed with him to defeat an invasion of Cybermen in league with industrialist Tobias Vaughan. In his final story
The War Games (1969), the Second Doctor's time came to an end when the TARDIS landed in the middle of a warzone, created by a race of alien warlords who, with the help of another renegade Time Lord the War Chief, progressively kidnapped and brainwashed humans into becoming soldiers for them, hoping to use the ones who survived to conquer the Galaxy. Although the Doctor was able to defeat their plan, he realised he would be unable to return the human subjects to their various original points in Earth's history. He therefore contacted the
Time Lords, sacrificing his own freedom in the process, and despite an attempt to escape was forced to return to his home planet. He was then put on trial by the Time Lords, for breaking their laws of non-interference. Despite the Doctor's argument that the Time Lords should use their great powers to help others, he was sentenced to exile on 20th century Earth, the Time Lords forcing his regeneration into the
Third Doctor in the process. Jamie and Zoe were returned to their own time, with their memories of all but their first encounter with the Doctor wiped and the secret of the TARDIS was also taken from the Doctor.
Season 6B Troughton's later appearances in multi-Doctor stories contain what would appear to be continuity errors. These include: • In The Five Doctors, Troughton's Doctor refers to events that happened in The War Games, his final story. • In The Two Doctors, Troughton's Doctor was on a mission from the Time Lords, although he was on the run from them throughout his era. Also, Jamie and The Doctor are both much older than during the Second Doctor era. This has caused some fans to speculate that the Doctor had many adventures in between series 6 and 7. According to this theory the Time Lords used the Second Doctor as an agent after the events of
The War Games (1969), and that he did not in fact immediately regenerate and enter his exile on Earth. This theory of continuity is described as "
Season 6B". Additionally, while
The War Games never depicted the Doctor's regeneration itself, it was later depicted in
TV Comic, which treated the exiled Doctor's exploits on Earth, before, in a comic entitled
The Nightwalkers, showing the Doctor dragged in to the TARDIS by animated
scarecrows, allowing his change of appearance to take place. The Second Doctor's regeneration was also depicted in
Devious, a fan-produced film starring
Jon Pertwee in his last appearance as the
Third Doctor. According to script editor
Robert Holmes, the Second Doctor's missions for the Time Lords took place prior to the events of
The War Games: "they 'framed' the Troughton Doctor and got him to do various things for them, and then hauled him up in front of them on trial. ==Personality==