The secret season known as "Season 6B" is an unusual part of Doctor Who history, and indeed the history of televised science fiction. It is notable for being one of the first fan theories in pop culture history, and one of the rare few to later be officially adopted (at least in part) by the writers of the show it was based on.
While it took the invention of the Internet for it to become a widely-known phenomena, fan-fiction has been around for decades. The term was first coined in relation to the original stories written for Star Trek fan magazines (or fanzines) in the 1960s. Some scholars have argued, however, that the phenomena may go back even further, making the case that Mark Twain's A Connecticut Yankee In King Arthur's Court might be considered an Arthurian legend fan-fic or that Dante's Divine Comedy is a crossover fan-fic of The Bible and Ancient Greek mythology.
Most professional writers today avoid reading fan-fiction based on their works for legal reasons. As such, it is exceedingly rare for a fan's ideas to be worked into a shared universe - even one as sizable as the reality of Doctor Who. That fact makes the story of Season 6B all the more remarkable. But in order to understand the idea of Season 6B, one must first know the history that led to its creation.
The War Games & The End Of The 2nd Doctor
"The War Games" was the final story of Doctor Who season 6 and the last televised storyline to focus on the adventures of the 2nd Doctor. These facts alone would mark it as historically notable, along with it being the last Doctor Who serial to be broadcast in black-and-white. In the context of The Doctor's adventures, however, "The War Games" was important because it was the first Doctor Who story to develop The Doctor's race and officially name them as the Time Lords.
The plot of "The War Games" found the Doctor and his companions, Zoe and Jamie, on a strange planet where World War I was being reenacted by abducted humans. It was quickly revealed that the area where the TARDIS landed was one of several similar "war zones" ruled over by a race of alien "War Lords," who were attempting to hone the surviving humans into a fighting force they could use to conquer the galaxy. To his horror, the Doctor realized that the leader of the War Lords, identified as the War Chief, was a member of his race.
Reluctantly, the Doctor contacted his homeworld and informed them of the War Chief's actions, which violated the Time Lord rules against interfering in the affairs of other races. Unfortunately, bringing the War Chief to justice for his crimes also required The Doctor be punished for his own interference, though his actions as he wandered the universe were intended to help others and preserve life. The Time Lords returned Jamie and Zoe to their proper times, erasing all their memories of their adventures with The Doctor beyond their first contact with him. The Doctor was then forced to regenerate into a new form and exiled to Earth, with all knowledge of how to pilot the TARDIS erased from his mind.
The Conflicts Of The 2nd Doctor's Later Appearances
Patrick Troughton returned to Doctor Who to recreate his role as the 2nd Doctor on several occasions. He appeared in "The Three Doctors" to mark the show's 10th anniversary, and in "The Five Doctors" for Doctor Who's 20th anniversary. He made one final appearance alongside the wildly dressed 6th Doctor, Colin Baker, in "The Two Doctors."
Fans noticed a number of conflicts between the 2nd Doctor's portrayal in these stories and the history established by "The War Games." For instance, the story of "The Three Doctors" had the 2nd Doctor brought forward in time by the Time Lords to assist his future self in combating the mad Time Lord founder Omega. The 2nd Doctor seemed oddly undisturbed by the fact that he was being ferried around time by the same Time Lords he'd hesitated in contacting in "The War Games."
"The Five Doctors" contained a number of other continuity problems. This story found the 2nd Doctor crashing a UNIT reunion party and meeting with his friend Brigadier General Lethbridge-Stewart in 1983, before the two were abducted along with other incarnations of The Doctor and his companions from across time and brought together on Gallifrey. It was never explained how the 2nd Doctor was able to transport himself to the reunion, as his incarnation lacked the ability to control when and where his TARDIS might wind up.
Later in "The Five Doctors," the 2nd Doctor and the Brigadier encountered Zoe and Jamie, seemingly trapped behind a deadly force-field. The 2nd Doctor quickly realized that his companions were an illusion because they shouldn't have recognized the Brigadier after having their memories erased by the Time Lords. This did nothing to explain why the 2nd Doctor knew this, however, since he was apparently regenerated into the 3rd Doctor just after Zoe and Jamie had their memories erased in "The War Games."
"The Two Doctors" contained all of these continuity problems and more, with the 2nd Doctor's hair now showing considerable signs of graying and Jamie no longer the teenager he had been when he originally traveled with The Doctor. The story once again had the 2nd Doctor working on behalf of the Time Lords (despite trying to avoid them all his life) and Jamie knowing precisely who the Time Lords were. Perhaps most confusingly, the 2nd Doctor's TARDIS had a completely different control room and he also had the ability to accurately travel through time and space, making reference to picking up Victoria (a companion he had before meeting Zoe) from where and when he had dropped her off to learn graphology.
Season 6B: The Secret Later Life of The 2nd Doctor
The obvious solution to these continuity conflicts was that there had to have been a series of 2nd Doctor stories set after "The War Games," but before the 3rd Doctor's first appearance in "Spearhead From Space." This was the only way to account for the 2nd Doctor and Jamie looking older, the Doctor's newfound ability to control the TARDIS and his apparent employment as an agent of the Time Lords. Yet this was impossible because the ending of "The War Games" seemed to definitively end the 2nd Doctor's adventures.
Enter Season 6B; a codified theory based on earlier fan theorizing, which was written up by Paul Cornell, Martin Day and Keith Topping as part of their Doctor Who episode guide, The Discontinuity Guide. The basic gist of the Season 6B Theory was that there was an entire season of unaired episodes set between "The War Games" and "Spearhead From Space" where the 2nd Doctor acted as an agent of the Time Lords in secret and was allowed to retrieve his companions. It was from this point in time that the 2nd Doctor encountered his 6th incarnation and was pulled forward in time to experience the events of "The Three Doctors" and "The Five Doctors."
The chief basis of the Season 6B Theory is that the body which puts the 2nd Doctor on trial in "The War Games" is called The Tribunal, not the High Council that was said to rule the Time Lords in later stories. The Tribunal also agreed, when the 2nd Doctor defended his actions as benevolent compared to the interference of the War Chief, that "there is evil in the universe that must be fought" and that the Doctor had a role to play in that battle.
The Season 6B Theory suggests that the Doctor's trial before the Tribunal was a show for the benefit of the High Council and that the Doctor was secretly put to work by a covert wing of the Time Lord government - possibly the Celestial Intervention Agency, which was later revealed to have manipulated many of the wanderings of the 4th Doctor. The 2nd Doctor continued his adventures in this capacity, gaining a greater control of the TARDIS during this time, before his original sentence was executed in earnest (presumably because he either rebelled against his CIA masters or because the High Council uncovered the deception).
Evidence of Season 6B in Later Stories
While not ever discussed on the show directly, the Season 6B Theory does seem to have been accepted into the Doctor Who canon by the BBC. Many of the articles from The Discontinuity Guide were later incorporated into the official Doctor Who website. This includes an entire page devoted to the Season 6B Theory.
Legendary Doctor Who writer and script editor Terrance Dicks, who wrote "The Five Doctors" and co-wrote "The War Games," was a notable proponent of the Season 6B Theory. Dicks' belief in the theory was so strong that he made it the basis of a 2005 novel he wrote for the Doctor Who Past Adventures line. The final book in Dicks' Players Trilogy, "World Game" follows directly after the events of "The War Games" and showed the 2nd Doctor being sent by the Celestial Intervention Agency to stop a group of time-manipulating immortals known as the Players from altering the course of the Napoleonic Wars. While the events of the Doctor Who novels are not held as canon by the BBC, the acceptance of the Season 6B Theory by a writer as prominent as Terrence Dicks did much to canonize it among Whovians.
More recently, the showrunners of Doctor Who have dropped hints of Season 6B's existence into the series proper. A montage during "The Name of the Doctor" showed Clara Oswald (who splintered herself across time to save The Doctor) manifesting in the middle of an apparent team-up between the 2nd and 8th Doctors - an event that could only have occurred during the Season 6B era. Finally, "The Timeless Children" confirmed the existence of another secretive branch of the Time Lord government known as the Division, whom the Timeless Child apparently worked for before becoming known as the Doctor. What connection the Division might have to the Celestial Intervention Agency is anyone's guess at this point, but it does seem to confirm the idea first proposed by the Season 6B Theory that the Doctor had long been manipulated by a secret faction of the Gallifreyian government, even as he worked for that same faction.