Much as I wanted to love this novel it just lacked something to rate more than three stars, despite the allure of its well depicted period setting, a range of characters that felt more authentic than is often the case in historical fiction, reasonably gripping serial killer plotline mixed with spies, astronomy and political intrigue in late 18th C London, portrayed with messy, smelly realism, a dark and dangerous place. A good edit would have improved the novel by tightening up the narrative- less digression, not quite so much detail, though I appreciate a lot of research clearly went into the writing, but in places there was simply too much information, to the detriment of narrative pace and holding the reader's attention.
I enjoyed the main character Jonathan Absey, a spy master who comes unstuck following the brutal murder of his young daughter by a Jack the Ripper style killer, and his older half-brother Alexander, a gay man in a harsh world where homosexuals risk public execution by hanging. The "voices" of these men are very well done indeed, though sometimes uncomfortable reading: the novel certainly goes for a warts & all approach that I found very refreshing, though other reviewers here have been put off by its spare-no-details take on sexuality and violence. I applaud any writer who goes against current orthodoxy that historical characters must think and act as though they have somehow anticipated 21st C attitudes so as not to 'offend' modern readers with outdated prejudices.
However, I guessed the identity of the killer early on, worked out who the mysterious Selene was, and then it all got a bit melodramatic towards the end. It was predictable, though I did enjoy parts of the novel very much. The exiled French aristocrat characters engaged in astronomy and espionage did not rise much above stereotype, and their part of the story failed to convince me.
Poor Jonathan Absey suffers a deal of misfortune as the story unfolds, his brother, too...and assorted red-headed young women who exist only to be victims, as required. Though the ending is predictable, or perhaps inevitable is a more accurate description, it also leaves unanswered questions, and I wondered if Redfern had hoped to write a sequel?
So, not a bad historical crime novel if you have a stomach for graphic detail and sexual violence (there are abusive relationships that could upset some readers). There is much to like in the shape of well realised time & place, flawed characters, and a dark, gritty story of love, obsession, intrigue, spies, secret messages and political skulduggery.