Day 166: The Evil of the Daleks Episode 4

So the Doctor has been forced to work for the Daleks as they search for the 'human factor' and so Jamie is used as an unwitting test subject in order to observe the behaviour of humans. But what makes this so well done is that the Doctor must keep this test a secret from his companion, and so he has to coerce him into doing the test (rescuing the daughter of one of the characters in the story from the clutches of the Daleks). The way that he does this is by making Jamie lose faith in the Doctor, and so he'll go forth and do the adventure by himself and not wait for the Doctor's orders. It's the sort of thing that could only happen at this point in the series, where Jamie has been not been in the series long enough to trust the Doctor no matter what, but it also has to be a fair way into the series such that Jamie's accusations of betrayal still hit hard, because the audience has grown to like Jamie over the past serials that he's been involved in, and to see him be betrayed by the Doctor is a saddening moment, even if you know that it is for the greater good. This also shows the hidden darkness of the Doctor, that occasionally the ends may have to justify the means, and what makes this more unsettling is that the ends haven't entirely been revealed to us. But we'll get to that tomorrow.