A good idea executed badly.

Essentially the entire first episode is just exposition, which is fine for a 4+ parter, but not so much in a 2-parter! I think it's as a result of that that the mystery aspect of the story suffers so much. It's not even that the pace is wrong so much as it just... glides over or entirely skips plot beats that are important to a mystery or thriller. But thank god, we get several whole minutes of the Doctor playing cricket! /s

I also wish the atmosphere had been darker, literally as well as figuratively. This would have benefited from a more Gothicky treatment, rather than one taking place entirely in sunlight. Even the secret passages were well-lit! I do appreciate a show that's light enough for me to see what's going on, and loathe the current trend of making everything dark, but this is a bit much.

The culprit's identity, while not obvious until it's revealed, prompted me to inwardly groan, "Of course it is." It's taken directly from a Sherlock Holmes story. Lazy setup and/or not enough development of that aspect of the backstory in episode 1. And while Sarah Sutton is fine as Ann, her acting is weirdly flat as Nyssa. The other three aren't on top of their acting games either.