Boy (Unnatural History)

A Little Brother of Faction Paradox once trapped the Doctor in a warehouse in San Francisco and tortured him. During torture, the Little Brother tampered with the Doctor's biodata, making him unable to percieve the colour violet. The Doctor finally made a deal with the Little Brother, the Doctor gave the Little Brother his Volkswagen Beetle so that he could scrap it and use the metal to create the same car in the past. In exchange for this the Little Brother left the Doctor alone and left to create the paradox. (EDA: Unnatural History)