In prison, Bates and the other inmates are doing this forced-march-in-a-circle "exercise," whereupon a friendly face tells Bates to search his cell when he returns there, as his cellmate is planning to set him up for something. Not sure what the point is when he's already serving a life sentence, but maybe he's trying to get Bates' dessert privileges revoked.
Mrs. Bartlett has apparently decided to open up to the trollop, as she tells her she was passing Vera's place on the fateful day and her door was open, so she looked in. Vera was cooking, but she had to post a letter so they walked out, whereupon she told Mrs. Bartlett that Bates was coming back later and she was jumpy and fearful, but determined. She goes on that Vera had made pastry and she was scrubbing it out of her nails "like she didn't care if she took the skin off." Well, that's... sane-sounding. Anna asks if she went home after posting the letter and Mrs. Bartlett confirms that, saying that in the light rain, there was sort of a halo around her. Anna can't resist a little sarcasm in response -- hard to blame her; she might hurt herself otherwise, to which I can attest -- but Mrs. Bartlett is genuinely upset at Vera's death, so it doesn't look like she's intentionally hiding anything. On the other hand, if Vera did cook something with poison in it to set her husband up, it would make sense for her to go to any lengths to remove the evidence from her fingers, no?
After a close-up on a Rolls Royce hood ornament, the Dowager Countess tells Sir Anthony, who is in the back seat with her, that it's kind of him to give them a ride. He calls up to Isobel that he wishes she had let him sit up front, but she tells him she prefers it and she's ridden in the front seat many times. I expect she's making a statement on how she's no aristocrat, but of course the Dowager Countess can't let that go: "Aren't you a wild thing!" If I make it to her age, I'm pretty sure I won't censor myself either. Some discussion about driving speeds leads to a typical age-difference comment from the Dowager Countess through which Sir Anthony chooses to smile and then, in response to a question from Isobel, the Dowager Countess says that the late Lord Grantham had shooting parties on the grounds of their destination. While it's nice as a retreat from the world, "I wouldn't have thought it suited to much else!" Well, retreat is kind of what the family is doing, so everything sounds very a propos!