The first of these, Moonflesh by Mark Morris was the last BF audio I wrote up before I got out of that habit. I wrote then:
Oh dear. There are some nice ideas in this Fifth Doctor / Nyssa audio; a country-house story in the same style as Black Orchid and The Unicorn and the Wasp, an alien which turns out to be a bit different from what we might have expected. But the guest characters are total cliches, including in particular Silver Crow, a mystical Native American played by a white English actor - that's the worst, though the doomed lesbian is pretty facepalming as well. The cast give it their best, but this should have been looked at more carefully before it was made.I liked it a bit more on second listening, but I don't think it's a brilliant start to the arc. I will say that the cast give it a decent push - Tim Bentinck (more recently a monk in TV story Extremis / The Pyramid at the End of the World, here proudly on the front cover), Hugh Fraser and indeed Francesca Hunt, whose character turns out not to be doomed after all. Just to add one important detail - set in 1911.
Tomb Ship, by Gordon Rennie and Emma Beeby, has one brilliant idea and one brilliant guest performance, and that makes it the best of these three. (I think it would work as a standalone too, as Hannah only appears rather late in the day.) It's the old storyline of explorers daring to tamper with a curséd tomb, except that the tomb is a pyramid in deep space (soundscape very well done), and the explorers have their own horrifying secret which only gradually becomes apparent. There is perhaps not quite enough plot for four episodes, but Eve Karpf is a real delight as the matriarch in control of the tomb raiders.
Masquerade, by Stephen Cole, starts off in a French château in 1770 and ends up somewhere else entirely. So does Hannah Bartholomew, who leaves the Tardis crew at the end in such a way that she's unlikely to return. There's a lot of good ideas here, with I felt slightly flawed execution - the awful threat didn't quite come across as sufficiently dreadful, and the linkage between 1770 and What Was Really Going On didn't quite work for me. Still, I may not have been paying enough attention, and the whole thing rounds off the trilogy suitably.
I felt that none of the three plays really stretched Davison or Sutton very much - they are both really good when pushed, but in all three cases they were more or less slotted into their usual roles here, apart from the first episode of Masquerade.