While this book proposes to be an account of the Diodati circle (meaning those who had in 1816 visited the Villa Diodati, including Mary Wollstonecraft Shelley, Percy Bysshe Shelley, Lord Byron, John William Polidori and Claire Clairmont), it's really a biography of Mary Wollstonecraft Shelley, with occasional forays into the lives of the others, most principally Claire Clairmont and Byron. A scant chapter is spared for poor, miserable Polidori-- not that anyone in this story escapes being poor or miserable in some form or fashion.

I say 'story', not 'history', because that's what this is. I'm no expert on this subject, so I can't tell if it's well researched; I assume it is, if only for the sheer volume of detail provided in the work. However, in the greatest weakness of the novel, authors Dorothy and Thomas Hoobler cannot resist the apparently overwhelming urge to weigh fact with a narrative, insert their opinions and suppositions, and weigh events down with their own leading lines. It's especially glaring because half the time I feel I would agree with their conclusions anyway, but it's grating to see them so casually thrown out, sometimes cruelly. The authors have sympathy for Mary Shelley and loathing for her husband and his friend Byron-- more than understandable, given their abysmal treatment of others, especially to Mary Shelley! But they take it a step further than it needs to go, with constant snide asides on the nature of relationships long over.

They tell more than they show, which is a horrible thing to say of a history, of nonfiction.

The book constantly details when and where Shelley got her inspiration for Frankenstein, as though they have authority on the subject. Of course, suppositions can be made based on historical evidence, but that's all they can be! Yet the authors constantly lead the reader to believe they know implicitly what Shelley meant.

Percy's changes to the manuscript also tended to justify Dr Frankenstein's behavior and portray him as the victim, rather than the creator of the evil. This reflected not only [Percy] Shelley's lack of awareness, but also his very similarity to Victor. Mary Shelley always saw that Frankenstein was deluding himself. So too was her husband.

[Harriet] had remarked to her sister, "I don't think I am made to inspire love, and you know my husband abandoned me." So on a gloomy, rainy day, Harriet acted on the suicidal impulses that she had entertained for a long time.

Mary [Shelley] was disduredbed that [Percy] Shelley and Claire [Clairmont] had k kept from her the secret of Claire's pregnancy for so long. Feeling shunted into the position of outsider, Mary would include secrecty among the suns that Victor Frankenstein committed in his pursuit of forbidden knowledge.

Not only does it make the story-- dramatic and turbulent enough-- morally shallow and saccharine, it often supposes that precisely everything of Mary Shelley's life went into her novels, which has the unfortunate and presumably unintended consequence of making it seen Shelley never had an original thought in her life. Which is ironic, considering the frankly insulting description of her only surviving son:

Percy Florence Shelley was elected to Parliment and received a knighthood-- respectability at last. As far as anybody knows, this son and grandson of four radical and creative individuals never had an original thought in his life.

Throughout the book, the Hooblers assume they are the arbiters of history, and present their theories and opinions with the weight of fact. It weakens the book immesurably, and I would not in good conscious recommend it to others interested in the subject.