This is a whodunnit with a conspiracy theory thrown in, set in a 1920s Agatha Christie/Dorothy L Sayers-type world of well-bred young ladies who take it upon themselves to do a bit of sleuthing.
Our heroine is posh Laetitia, an amateur archaeologist, who goes to France to investigate her godfather's murder. Tracking down the killer involves not only solving the mystery of a hidden tomb, but also foiling a sinister plot by a local aristocrat to restore France to its former glory. It has a very old fashioned feel about it and could almost have been written in the twenties, which is presumably what the author was going for.
It's readable, it's an interesting setting, but these don't seem like real people and it's hard to believe a word of it. And there are some faults which really jarred throughout.
Firstly, the author's been too ambitious with the tiresome Mary Magdalene/ancient earth goddess conspiracy plot (yes, here we are in Dan Brown territory yet again). A nice, straightforward murder mystery with a bit of political shenanigans would have worked so much better: it's the twenties, after all, so there's plenty to draw from - people are still dealing with the fallout from the first world war, while events leading up to the next one are shaping up.
Secondly, the dialogue. Every single character speaks in long and very grammatically correct sentences and everyone sounds exactly the same.
And finally, it's very hard to care about a heroine like Laetitia - beautiful, clever and popular (is there any man under the age of 80 in this French village who doesn't instantly fall in love with her?) but also smug, superior, and very, very annoying. Making her a bit more human would have added a much needed dose of realism to this story. I'd actually have preferred it if her sidekick Gunning was the protagonist. He's a much more interesting and sympathetic character.
It's an OK read, just scraping three stars for me. I'll have to try her other books - this seems to be considered the worst of the bunch.