Some 20+ years after the fact, Sylvester McCoy (the Seventh Doctor) has claimed that anti-Thatcher plot lines were woven into the series just after Thatcher’s re-election in 1987. As mentioned in this article in the Telegraph, and now made public for the first time by McCoy, this “news” seems to be news to everyone at the BBC except those involved in the production back in the late 80’s. McCoy told the Sunday Times that there seemed to be a feeling on the set that Margaret Thatcher was a far worse monster than anything the Doctor could ever encounter and that “it seemed the right thing to do“. Script editor at the time, Andrew Cartmel, verified the claim saying that it was almost considered a job requirement on the set to detest Thatcher.