Here we have the collection of notes, messages, emails and more put together by a non-fiction author, commissioned to write a true crime book on a terrible event from eighteen years earlier. A cult had persuaded a 17-year-old that her baby was evil. On the night of the great conjunction of the planets, it was to be sacrificed to save the world by deluded individuals who believe themselves to be angels in human form. Yet all but one of these 'archangels' appear to have killed themselves, while the last of them, Gabriel, is jailed for life for his part in their deaths, and the murder of an apparently unconnected man.
As was the case with the earlier books, the collection of documents and messages allows us to gain an idea of the character of the author, Amanda Bailey, and also brings in other authors working on the same series, a rival of Bailey's also writing about the Alperton Angels (because the unidentified baby should now be 18) and a motley collection of aging police officers, would-be amateur sleuths and more.
Things are inevitably all not what they seem - and with her usual skill, Hallett prevents the reader from spotting this until all is revealed. It is absolutely brilliant. Packed with twists, but also fascinating details. At first it seems as if it's going to be far too complicated to get your head around, especially as there are conflicting stories about what really happened, yet such is Hallett's skill as a writer than you never lose the thread and everything eventually opens up to reveal the complex workings within.
Less far fetched in plot than The Twyford Code, this is as near perfection as you get. I see Hallett has another title due out in 2024 (and yes, I've already pre-ordered it). Can she keep this up? I really hope so.