Summary
Doctor Who's First and Second Doctors were color-blind, according to the novelization of the 50th anniversary episode. This explains why their episodes were in black and white.
The color-blind reveal has significant ramifications for the show, implying that the audience perceives Doctor Who from the Doctor's perspective. Consequently, the narratives could be partial or intentionally modified.
This theory remains applicable in multi-Doctor episodes featuring the First and Second Doctors in color, as these stories are presented from the viewpoint of the present Doctor.
The First and Second Doctors were confined to black and white adventures, but Doctor Who cleverly justified this. Premiering in 1963 when televisions were not yet common, Doctor Who embarked on its enduring journey through time and space without color. From the TARDIS' initial appearance in Totter's Lane to the vivid transformation of Patrick Troughton's Second Doctor, the iconic sci-fi phenomenon remained in grayscale.
It wasn't until Jon Pertwee's Third Doctor emerged from the TARDIS in "Spearhead From Space" in 1970 that Doctor Who embraced vibrant colors. Interestingly, Doctor Who never felt compelled to explicitly address or explain this change. When the First and Second Doctors made subsequent appearances in later years, they did so in full color. Nonetheless, Doctor Who has somewhat offered an in-universe justification for the monochromatic portrayal of the First and Second Doctor eras.
Doctor Who's First & Second Doctors Were Actually Color-Blind
In the novelization of "The Day of the Doctor," the 50th anniversary episode of Doctor Who, then-showrunner Steven Moffat reveals that the first two iterations of the Time Lord played by William Hartnell and Patrick Troughton were unable to perceive color. A section in the book describes the regeneration of the Eighth Doctor into the War Doctor, portrayed by John Hurt, and delves into how the character's eyesight changes with each new body. During his initial two forms, the Doctor could only see the world in black and white, and he occasionally longed for the simplicity of that monochrome existence. It took him many centuries to realize that he had been color-blind.
The revelation serves as a clear allusion to the 1960s era of Doctor Who, subtly aiming to justify why the First and Second Doctor episodes were presented in black and white, while the Third Doctor and subsequent regenerations enjoyed color episodes. Interestingly, this explanation can also be construed as a response to Doctor Who's gradual shift from grainy 1970s picture quality to modern HD, as indicated by the line, "Oh, the color balance was wildly different yet again." Although not to be taken entirely seriously, Moffat's portrayal of the Doctor's changing eyesight with each regeneration effectively functions as an in-universe method of rationalizing the radical aesthetic variations across different Doctor Who eras.
Doctor Who's Color-Blind Reveal Completely Changes The Show
Considering Doctor Who's color-blind rationalization seriously, the repercussions of this revelation are significant for the show. If the black and white portrayal of 1960s Doctor Who episodes was due to the First and Second Doctors' color-blindness, it implies that the audience experiences Doctor Who through the perspective of the Doctor rather than a neutral, third-person view. Consequently, Doctor Who's narratives are shaped by the Doctor's subjective perception, encompassing their biases, fallible memories, and potentially intentional deceit.
The Doctor's portrayal in Doctor Who may not be entirely truthful, akin to a winner who alters history to appear better. It is possible that the Doctor seems heroic because they act as both the protagonist and the narrator. This theory becomes more complicated when considering episodes featuring multiple Doctors, such as the First and Second Doctors appearing in color. However, the theory still holds true. One could argue that these stories are told solely from the perspective of the current Doctor. This explanation accounts for instances like the Second Doctor appearing in color alongside the Sixth Doctor in "The Two Doctors" from 1985, as the story is told from the perspective of the latter.