Episodes 6, 7, and 8 respectively.
In "Gelignite," we deal with the fact that Princess Margaret's romance with Peter Townsend (not that Peter Townsend) has become public knowledge/scandal depending on your point of view. The fact that Townsend is divorced is an issue because the church doesn't acknowledge remarriage if both parties are still living. The loophole: Once Margaret reaches the age of 25, she can marry without Elizabeth's permission. This also allows Elizabeth to save face because she does not have to make an unpopular decision in order to please her sister. Of course, she then goes on to upset Margaret anyway by sending Townsend to Brussels so things can cool off for a bit while Margaret literally waits to grow up.
We then move on to "Scientia Potentia Est" (it means "knowledge is power"). Elizabeth is feeling the lack of her overall education. Oh, she had a tutor as a kid and all that, but she mostly learned, uh... Decorum? And probably a lot of history and all about how Parliament works or whatever. But because there was so much focus on those things, her general curriculum suffered. So she decides to employ a new tutor to help her with things like science so that she can understand things like atomic bombs. Not a bad idea, really. Meanwhile, Churchill is practically in a sitcom as he tries to hide his illness from Elizabeth as well as that of the Foreign Secretary. Of course they get caught and dressed down for it. That's how sitcoms work. Oh, and Elizabeth really wants Martin to come be her new Personal Secretary but she's told that Martin is only a junior and she has to promote the senior to the job. Because even though she's The Queen, she's not allowed to do end runs around the proper form and order of things. Hierarchy, you know. The system—and monarchy—relies on it.
Remember way back when Liz and Phil were doing that big tour because her dad was too ill to do it? But then he died and so she had to go home and be Queen? Yeah, so in "Pride & Joy" it's decided she and Phillip should go finish that tour. They're going to be gone for three months, meaning the Queen Mother and Princess Margaret will be filling in back home. Except the Queen Mother up and leaves for Scotland and Margaret acts more like a wannabe movie star than royalty by drawing a lot of attention to herself. Liz wrestles with a certain amount of envy at how loved Margaret seems to be by the public. She also knows that the monarchy is not meant to be the spectacle Margaret is making of it, and she tells Margaret as much upon returning home. Margaret accuses Elizabeth of being too perfect. Meanwhile, the episode title is explained in that their father used to call Elizabeth his pride and Margaret his joy. Though to hear Margaret tell it, he used "but" instead of "and." Because Margaret firmly believes she was daddy's favorite and is mean enough to fling that in her sister's face.
So that's that for those three episodes. Only two more this season. It continues to be fun, though I'm waiting for Phillip to get in trouble with that club he keeps hanging out with. Nothing worse than a bunch of bored, wealthy men.